Method of Maintaining Constant Movement of a Cutting Blade of an Ultrasonic Waveguide

ABSTRACT

A method of maintaining a constant movement of a cutting blade of an ultrasonic waveguide includes providing an ultrasonic transducer operable to convert a received motional current into a movement of a cutting blade of an ultrasonic waveguide, a measurement circuit connected in a parallel configuration with the ultrasonic transducer, and a variable power source operable to supply current through a set of connection points to the parallel configuration and thereby create the motional current in the ultrasonic transducer. Current is supplied through a set of connection points of the parallel configuration with the variable power source to, thereby, create the motional current in the ultrasonic transducer and the motional current is regulated with a current controller by varying an output of the power source, thereby maintaining a substantially constant rate of movement of the cutting blade across a variety of cutting loads.

CROSS-REFERENCE TO RELATED APPLICATION

This application is:

-   a divisional of U.S. patent application Ser. Nos. 13/072,187, filed    on Mar. 25, 2011;-   a continuation-in-part of U.S. patent application Ser. Nos.    12/266,101 filed on Nov. 6, 2008; 12/266,146 filed on Nov. 6, 2008;    12/266,226 filed on Nov. 6, 2008; 12/266,252 filed on Nov. 6, 2008;    12/266,320 filed on Nov. 6, 2008; 12/266,664 filed on Nov. 7, 2008;    12/269,544 filed on Nov. 12, 2008; 12/269,629 filed on Nov. 12,    2008; and 12/270,146 filed on Nov. 13, 2008 (which applications each    claim priority to U.S. Provisional Application Ser. Nos. 60/991,829    filed on Dec. 3, 2007; 60/992,498 filed on Dec. 5, 2007; 61/019,888    filed on Jan. 9, 2008; 61/045,475 filed on Apr. 16, 2008; 61/048,809    filed on Apr. 29, 2008; and 61/081,885 filed on Jul. 18, 2008);-   is a divisional of U.S. patent application Ser. Nos. 12/547,898,    12/547,975, and 12/547,999, all filed on Aug. 26, 2009; and-   is a divisional of U.S. patent application Ser. No. 13/072,373,    filed on Mar. 25, 2011;-   is a divisional of U.S. patent application Ser. No. 13/072,309,    filed on Mar. 25, 2011;-   is a divisional of U.S. patent application Ser. No. 13/072,345,    filed on Mar. 25, 2011;-   is a divisional of U.S. patent application Ser. No. 13/072,247,    filed on Mar. 25, 2011;-   is a divisional of U.S. patent application Ser. No. 13/072,273,    filed on Mar. 25, 2011;-   is a divisional of U.S. patent application Ser. No. 13/072,221,    filed on Mar. 25, 2011,    the entire disclosures of which are all hereby incorporated herein    by reference in their entireties.

FIELD OF THE INVENTION

The present invention relates generally to an ultrasonic surgicalassembly and, more particularly, relates to a method of maintainingconstant movement of a cutting blade of an ultrasonic waveguide, inparticular, in a cordless, hand-held, fully electrically powered andcontrolled, surgical ultrasonic cutting device.

DESCRIPTION OF THE RELATED ART

Ultrasonic instruments are effectively used in the treatment of manymedical conditions, such as removal of tissue and cauterization ofvessels. Cutting instruments that utilize ultrasonic waves generatevibrations with an ultrasonic transducer along a longitudinal axis of acutting blade. By placing a resonant wave along the length of the blade,high-speed longitudinal mechanical movement is produced at the end ofthe blade. These instruments are advantageous because the mechanicalvibrations transmitted to the end of the blade are very effective atcutting organic tissue and, simultaneously, coagulate the tissue usingthe heat energy produced by the ultrasonic frequencies. Such instrumentsare particularly well suited for use in minimally invasive procedures,such as endoscopic or laparoscopic procedures, where the blade is passedthrough a trocar to reach the surgical site.

For each kind of cutting blade (e.g., length, material, size), there areone or more (periodic) driving signals that produce a resonance alongthe length of the blade. Resonance results in optimal movement of theblade tip and, therefore, optimal performance during surgicalprocedures. However, producing an effective cutting-blade driving signalis not a trivial task. For instance, the frequency, current, and voltageapplied to the cutting tool must all be controlled dynamically, as theseparameters change with the varying load placed on the blade and withtemperature differentials that result from use of the tool.

FIG. 1 shows a block schematic diagram of a prior-art circuit used forapplying ultrasonic mechanical movements to an end effector. The circuitincludes a power source 102, a control circuit 104, a drive circuit 106,a matching circuit 108, a transducer 110, and also includes a handpiece112, and a waveguide 114 secured to the handpiece 112 (diagrammaticallyillustrated by a dashed line) and supported by a cannula 120. Thewaveguide 114 terminates to a blade 116 at a distal end. A clampingmechanism, referred to as an “end effector” 118, exposes and enables theblade portion 116 of the waveguide 114 to make contact with tissue andother substances. Commonly, the end effector 118 is a pivoting arm thatacts to grasp or clamp onto tissue between the arm and the blade 116.However, in some devices, the end effector 118 is not present.

The drive circuit 104 produces a high-voltage self-oscillating signal.The high-voltage output of the drive circuit 104 is fed to the matchingcircuit 108, which contains signal-smoothing components that, in turn,produce a driving signal (wave) that is fed to the transducer 110. Theoscillating input to the transducer 110 causes the mechanical portion ofthe transducer 110 to move back and forth at a magnitude and frequencythat sets up a resonance along the waveguide 114. For optimal resonanceand longevity of the resonating instrument and its components, thedriving signal applied to the transducer 110 should be as smooth a sinewave as can practically be achieved. For this reason, the matchingcircuit 108, the transducer 110, and the waveguide 114 are selected towork in conjunction with one another and are all frequency sensitivewith and to each other.

Because a relatively high-voltage (e.g., 100 V or more) is required todrive a typical piezoelectric transducer 110, the power source that isavailable and is used in all prior-art ultrasonic cutting devices is anelectric mains (e.g., a wall outlet) of, typically, up to 15A, 120 VAC.Therefore, all known ultrasonic cutting devices resemble that shown inFIGS. 1 and 2 and utilize a countertop box 202 with an electrical cord204 to be plugged into the electrical mains 206 for supply of power.Resonance is maintained by a phase locked loop (PLL), which creates aclosed loop between the output of the matching circuit 108 and the drivecircuit 106. For this reason, in prior art devices, the countertop box202 always has contained all of the drive and control electronics 104,106 and the matching circuit(s) 108. A typical retail price for suchboxes is in the tens of thousands of dollars.

A supply cord 208 delivers a sinusoidal waveform from the box 202 to thetransducer 110 within the handpiece 112 and, thereby, to the waveguide114. The prior art devices present a great disadvantage because the cord208 has a length, size, and weight that restricts the mobility of theoperator. The cord 208 creates a tether for the operator and presents anobstacle for the operator and those around him/her during any surgicalprocedure using the handpiece 112. In addition, the cord must beshielded and durable and is very expensive.

Another disadvantage exists in the prior art due to the frequencysensitivity of the matching circuit 108, the transducer 110, and thewaveguide 114. By having a phase-locked-loop feedback circuit betweenthe output of the matching circuit 108 and the drive circuit 104, thematching circuit 108 is required always to be located in the box 202,near the drive circuit 108, and separated from the transducer 110 by thelength of the supply cord 208. This architecture introduces transmissionlosses and electrical parasitics, which are common products ofultrasonic-frequency transmissions.

In addition, prior-art devices attempt to maintain resonance at varyingwaveguide 114 load conditions by monitoring and maintaining a constantcurrent applied to the transducer. However, the only predictablerelationship between current applied to the transducer 110 and amplitudeis at resonance. Therefore, with constant current, the amplitude of thewave along the waveguide 114 is not constant across all frequencies.When prior art devices are under load, therefore, operation of thewaveguide 114 is not guaranteed to be at resonance and, because only thecurrent is being monitored and held constant, the amount of movement onthe waveguide 114 can vary greatly. For this reason, maintainingconstant current is not an effective way of maintaining a constantmovement of the waveguide 114.

Furthermore, in the prior art, handpieces 112 and transducers 110 arereplaced after a finite number of uses, but the box 202, which is vastlymore expensive than the handpiece 112, is not replaced. As such,introduction of new, replacement handpieces 112 and transducers 110frequently causes a mismatch between the frequency-sensitive components(108, 110, and 112), thereby disadvantageously altering the frequencyintroduced to the waveguide 114. The only way to avoid such mismatchesis for the prior-art circuits to restrict themselves to precisefrequencies. This precision brings with it a significant increase incost.

Some devices claim to be able to contain all necessary components forultrasonic procedures within a single handle. These devices, however, donot currently appear in the marketplace and the written descriptions ofeach disclose virtually no details of how their circuitry is enabled. Atleast one such device is described as being completely sealed and all ofthe device's electronic components, such as the power supply and thetransducer, are non-replaceable. This design is self-evident, becausethe tool, used in surgery, must be sterilizable. However, in somesurgeries, a cutting tool reaches its maximum lifespan within very fewsurgeries or, in some cases, even before the surgery is finished. With asealed device design, the entire device must be disposed, including itsexpensive internal components.

In addition, this device is described as using inductive charging. Itwas not designed or envisioned to use modern, long-lasting, high-powerbatteries, such as lithium-ion (Li) batteries. As is known in the art,Lithium batteries cannot be charged in a series configuration ofmultiple cells. This is because, as the voltage increases in aparticular cell, it begins to accept charging energy faster than theother lower-voltage cells. Therefore, each cell must be monitored sothat a charge to that cell can be controlled individually. When aLithium battery is formed from a group of cells, a multitude of wiresextending from the exterior of the device to the battery is needed.Sakurai cannot provide this necessary feature because, by design, thesealed autoclavable Sakurai device does not and cannot have a pluralityof external exposed contacts to be coupled to a charging device. Infact, the inductive charging feature for the sealed device is entirelyat odds with exposed contacts.

Therefore, a need exists to overcome the problems associated with theprior art, for example, those discussed above.

SUMMARY OF THE INVENTION

Briefly, in accordance with exemplary embodiments of the presentinvention, a cordless handheld apparatus that is capable of performingcontinuous ultrasonic cutting and cauterizing is disclosed. Theinvention includes a power supply, a control circuit, a drive circuit,and a matching circuit—all located within a handpiece of the ultrasoniccutting device and all operating and generating waveforms at batteryvoltages. Advantageously, the invention allows components to be replacedor moved between different devices.

The present invention, according to several embodiments, allowscomponents of the device to be removed, replaced, serviced, and/orinterchanged. Some components are “disposable,” which, as used herein,means that the component is used for only one procedure and is thendiscarded. Still other components are “reusable,” which, as used herein,means that the component can be aseptically cleaned and then used for atleast a second time. As will be explained, other components are providedwith intelligence that allows them to recognize the device to which theyare attached and to alter their function or performance depending onseveral factors.

The invention provides a method of maintaining constant movement of acutting blade of an ultrasonic waveguide that overcomes thehereinafore-mentioned disadvantages of the heretofore-known devices andmethods of this general type and that require disposal of and preventadvantageous reuse of costly components.

With the foregoing and other objects in view, there is provided, inaccordance with the invention, a method of maintaining a constantmovement of a cutting blade of an ultrasonic waveguide includesproviding an ultrasonic transducer operable to convert a receivedmotional current into a movement of a cutting blade of an ultrasonicwaveguide and a measurement circuit connected in a parallelconfiguration with the ultrasonic transducer. Current is suppliedthrough a set of connection points of the parallel configuration withthe variable power source to, thereby, create the motional current inthe ultrasonic transducer and the motional current is regulated with acurrent controller by varying an output of the power source, therebymaintaining a substantially constant rate of movement of the cuttingblade across a variety of cutting loads.

With the foregoing and other objects in view, there is also provided, inaccordance with the invention, a method of maintaining a constantmovement of a cutting blade of an ultrasonic waveguide includesproviding an ultrasonic transducer operable to convert a receivedmotional current into a movement of a cutting blade of an ultrasonicwaveguide, the ultrasonic transducer having a first capacitance in aparallel configuration with a series configuration of a resistance, aninductance and a second capacitance, whereby the motional current flowsthrough the series configuration and a third capacitance in a parallelconfiguration with the first capacitance. Current is supplied through aset of connection points of the parallel configuration with a variablepower source coupled to the third capacitance and the ultrasonictransducer to, thereby, create the motional current in the ultrasonictransducer and the motional current is regulated with a currentcontroller by varying an output of the power source based upon a productof the current flowing through the third capacitance multiplied by aratio between a value of the first capacitance and a value of the thirdcapacitance subtracted from a total current flowing into the ultrasonictransducer, thereby maintaining a substantially constant rate ofmovement of the cutting blade across a variety of cutting loads.

With the foregoing and other objects in view, there is also provided, inaccordance with the invention, a method of maintaining a constantmovement of a cutting blade of an ultrasonic waveguide includesproviding an ultrasonic transducer operable to convert a receivedmotional current into a movement of a cutting blade of an ultrasonicwaveguide, a removable battery, a disposable handle body with a portiondefining a battery-holding compartment shaped to removably receive thebattery therein and operable to removably couple the ultrasonictransducer to the ultrasonic waveguide, the ultrasonic transducer beingseparable from the handle body, the ultrasonic transducer having a firstcapacitance in a parallel configuration with a series configuration of aresistance, an inductance and a second capacitance, whereby the motionalcurrent flows through the series configuration, and a third capacitancein a parallel configuration with the first capacitance. Current issupplied through a set of connection points of the parallelconfiguration with a variable power source coupled to the thirdcapacitance and the ultrasonic transducer to, thereby, create themotional current in the ultrasonic transducer and the motional currentis regulated with a current controller by varying an output of the powersource based upon a product of the current flowing through the thirdcapacitance multiplied by a ratio between a value of the firstcapacitance and a value of the third capacitance subtracted from a totalcurrent flowing into the ultrasonic transducer, thereby maintaining asubstantially constant rate of movement of the cutting blade across avariety of cutting loads.

With the foregoing and other objects in view, there is also provided, inaccordance with the invention, a method of maintaining a constantmovement of a cutting blade of an ultrasonic waveguide includesproviding an ultrasonic transducer operable to convert a receivedmotional current into a movement of a cutting blade of an ultrasonicwaveguide and a measurement circuit connected in a parallelconfiguration with the ultrasonic transducer, supplying current througha set of connection points of the parallel configuration with thevariable power source to, thereby, create the motional current in theultrasonic transducer, the variable power source comprising a removablebattery, and regulating the motional current with a current controllerby varying an output of the power source, thereby maintaining asubstantially constant rate of movement of the cutting blade across avariety of cutting loads.

In accordance with another mode of the invention, the ultrasonictransducer has a first capacitance in a parallel configuration with aseries configuration of a resistance, an inductance, and a secondcapacitance and the motional current flows through the seriesconfiguration.

In accordance with a further mode of the invention, the measurementcircuit is comprised of a third capacitance in a parallel configurationwith the first capacitance.

In accordance with an added mode of the invention, the variable powersource is coupled to the third capacitance and the ultrasonictransducer.

In accordance with an additional mode of the invention, the motionalcurrent regulating step is carried out by varying an output of the powersource based upon a product of the current flowing through the thirdcapacitance multiplied by a ratio between a value of the firstcapacitance and a value of the third capacitance subtracted from a totalcurrent flowing into the ultrasonic transducer.

In accordance with yet another mode of the invention, the currentcontroller comprises a processor and the variable power source comprisesa phase locked loop communicatively coupled to the processor, and thereare provided the steps of determining a frequency of movement of thecutting blade with the phase locked loop and storing a last frequency ofblade movement in a memory communicatively coupled to the processor.

In accordance with yet a further mode of the invention, a clampingmechanism having a range of clamping force values is provided and isoperable to place material in physical contact with the cutting blade,the current controller is communicatively coupled to the clampingmechanism, and the motional current is varied with the currentcontroller based upon a given clamping value within the range ofclamping values.

In accordance with yet an added mode of the invention, the variablepower source comprises a removable battery.

In accordance with a concomitant mode of the invention, a disposablehandle body is provided with a portion defining a battery-holdingcompartment having at least two battery contacts, a waveguide attachmentdock exposed to the environment and shaped to accept the ultrasonicwaveguide therein, a transducer attachment dock exposed to theenvironment and shaped to place the ultrasonic transducer in coaxialalignment with the ultrasonic waveguide when the ultrasonic waveguide isdisposed within the waveguide attachment dock, and anultrasonic-signal-generator assembly dock exposed to the environment andshaped to substantially simultaneously selectively removably secure atleast the ultrasonic transducer to the handle body, place an end of theultrasonic transducer within the transducer attachment dock, andelectrically couple at least the ultrasonic transducer to the at leasttwo battery contacts.

Although the invention is illustrated and described herein as embodiedin a method of maintaining constant movement of a cutting blade of anultrasonic waveguide, it is, nevertheless, not intended to be limited tothe details shown because various modifications and structural changesmay be made therein without departing from the spirit of the inventionand within the scope and range of equivalents of the claims.Additionally, well-known elements of exemplary embodiments of theinvention will not be described in detail or will be omitted so as notto obscure the relevant details of the invention.

While the specification concludes with claims defining the features ofthe invention that are regarded as novel, it is believed that theinvention will be better understood from a consideration of thefollowing description in conjunction with the drawing figures, in whichlike reference numerals are carried forward. Accordingly, the apparatuscomponents and method steps have been represented where appropriate byconventional symbols in the drawings, showing only those specificdetails that are pertinent to understanding the embodiments of thepresent invention so as not to obscure the disclosure with details thatwill be readily apparent to those of ordinary skill in the art havingthe benefit of the description herein.

Other features that are considered as characteristic for the inventionare set forth in the appended claims. As required, detailed embodimentsof the present invention are disclosed herein; however, it is to beunderstood that the disclosed embodiments are merely exemplary of theinvention, which can be embodied in various forms. Therefore, specificstructural and functional details disclosed herein are not to beinterpreted as limiting, but merely as a basis for the claims and as arepresentative basis for teaching one of ordinary skill in the art tovariously employ the present invention in virtually any appropriatelydetailed structure. Further, the terms and phrases used herein are notintended to be limiting; but rather, to provide an understandabledescription of the invention. While the specification concludes withclaims defining the features of the invention that are regarded asnovel, it is believed that the invention will be better understood froma consideration of the following description in conjunction with thedrawing figures, in which like reference numerals are carried forward.The figures of the drawings are not drawn to scale.

DETAILED DESCRIPTION OF THE DRAWINGS

The accompanying figures, where like reference numerals refer toidentical or functionally similar elements throughout the separate viewsand which together with the detailed description below are incorporatedin and form part of the specification, serve to further illustratevarious embodiments and to explain various principles and advantages allin accordance with the present invention.

FIG. 1 is a diagrammatic illustration of components of a prior-artultrasonic cutting device with separate power, control, drive andmatching components in block diagram form.

FIG. 2 is a diagram illustrating the prior-art ultrasonic cutting deviceof FIG. 1.

FIG. 3 is a block circuit diagram of an ultrasonic cutting device inaccordance with an exemplary embodiment of the present invention.

FIG. 4 is graph illustrating a square waveform input to the matchingcircuit in accordance with an exemplary embodiment of the presentinvention.

FIG. 5 is graph illustrating a sinusoidal waveform output from thematching circuit in accordance with an exemplary embodiment of thepresent invention.

FIG. 6 is a diagrammatic illustration of the effect that a resonant sinewave input to a transducer has on a waveguide of the ultrasonic cuttingdevice in accordance with an exemplary embodiment of the presentinvention with the sinusoidal pattern shown representing the amplitudeof axial motion along the length of the waveguide.

FIG. 7 is a fragmentary, schematic circuit diagram of an elementalseries circuit model for a transducer in accordance with an exemplaryembodiment of the present invention.

FIG. 8 is a fragmentary, schematic circuit diagram of an inventivecircuit with the circuit of FIG. 7 and is useful for monitoring amotional current of a transducer in accordance with an exemplaryembodiment of the present invention.

FIG. 9 is a fragmentary, schematic circuit diagram of an elementalparallel circuit model of a transducer in accordance with an exemplaryembodiment of the present invention.

FIG. 10 is fragmentary, schematic circuit diagram of an inventivecircuit with the circuit of FIG. 9 and is useful for monitoring themotional current of a transducer in accordance with an exemplaryembodiment of the present invention.

FIG. 11 is a fragmentary, schematic circuit diagram of an inventivecircuit with the circuit of FIG. 7 and is useful for monitoring themotional current of a transducer in accordance with an exemplaryembodiment of the present invention.

FIG. 12 is a fragmentary, schematic circuit diagram of an inventivecircuit with the circuit of FIG. 9 and is useful for monitoring themotional current of a transducer in accordance with an exemplaryembodiment of the present invention.

FIG. 13 is a side elevational view of a left side of an ultrasoniccutting device handle with fully integrated control, drive and matchingcomponents and removable transducer and power supply in accordance withan exemplary embodiment of the present invention.

FIG. 14 is a side elevational view of the exemplary handle of FIG. 13with the left-side shell removed and with the upper slide cover removedto show the integrated control, drive and matching components andremovable power supply therein in accordance with an exemplaryembodiment of the present invention.

FIG. 15 is a perspective view of a transducer assembly removed from theexemplary handle of FIG. 14 in accordance with an exemplary embodimentof the present invention.

FIG. 16 is a perspective and partially hidden view of the transducerassembly of FIG. 15 in accordance with an exemplary embodiment of thepresent invention.

FIG. 17 is a perspective and partially hidden view of the pack shown inthe handle of FIG. 14 in accordance with an exemplary embodiment of thepresent invention.

FIG. 18 is a side elevational view of a left side of an ultrasoniccutting device capable of holding in a top area a reusable pack thatincludes the battery, circuitry, and the transducer in accordance withan exemplary embodiment of the present invention.

FIG. 19 is a side elevational view of a left side of the ultrasoniccutting device of FIG. 18 showing the access door in accordance with anexemplary embodiment of the present invention.

FIG. 20 is the removable, reusable pack used in the device shown in FIG.18 and includes a battery, control circuit, drive circuit, matchingcircuit, and transducer.

FIG. 21 is a side elevational view of a left side of an ultrasoniccutting device handle with fully integrated control, drive and matchingcomponents and removable power supply in accordance with an exemplaryembodiment of the present invention.

FIG. 22 is a side elevational view of the exemplary handle of FIG. 21with the left-side shell removed and with the upper slide cover removedto show the integrated control, drive and matching components andremovable power supply therein.

FIG. 23 is a side elevational view of a left side of an ultrasoniccutting device handle with fully integrated control, drive and matchingcomponents, and transducer in a removable module and also a removablebattery pack in accordance with an exemplary embodiment of the presentinvention.

FIG. 24 is a side elevational view of the exemplary handle of FIG. 23with the left-side shell removed and with the upper slide cover removedto show the integrated control, drive and matching components andremovable power supply therein.

FIG. 25 is a side elevational view of an exemplary handle with theleft-side shell removed to show a TAG, a removable power supply, and ablade and waveguide attached to the spindle in accordance with anexemplary embodiment of the present invention.

FIG. 26 is a side elevational view of an exemplary handle with theleft-side shell removed to show electronic coupling between thegenerator and transducer assembly of the TAG in accordance with anexemplary embodiment of the present invention.

FIG. 27 is an enlarged side elevational view of the exemplary handle ofFIG. 23 from the left side thereof with the left-side shell, the slidecover, and the battery pack removed, and with the trigger in anintermediate actuated position.

FIG. 28 is an enlarged side elevational view of the exemplary handle ofFIG. 23 from the right side thereof with the right-side shell, the slidecover, and the battery pack removed, and with the trigger in a fullyactuated position.

FIG. 29 is an enlarged side elevational view of the exemplary handle ofFIG. 23 from the left side thereof with the shell and left-side slidecover removed.

FIG. 30 is an enlarged side elevational view of the exemplary handle ofFIG. 29 from the right side thereof also with internal triggercomponents removed.

FIG. 31 is a perspective view from the front left side of a hand-heldultrasonic cutting pen device with fully integrated control, drive andmatching components and removable power supply in accordance with anexemplary embodiment of the present invention.

FIG. 32 is a side elevational view of the hand-held ultrasonic cuttingpen device of FIG. 21 from the left side.

FIG. 33 is a side elevational view of the hand-held ultrasonic cuttingpen device of FIG. 32 with the left-side shell removed.

FIG. 34 is a diagrammatic illustration of a hand-held ultrasonic cuttingpen device to be connected to a man-portable, control and power supplyassembly in accordance with an exemplary embodiment of the presentinvention.

FIG. 35 is a perspective view of a hand-held ultrasonic cutting pendevice to be connected to a man-portable, control and power supplyassembly in accordance with an exemplary embodiment of the presentinvention.

FIG. 36 is a perspective view of the hand-held ultrasonic cutting pendevice of FIG. 35 with a left-half shell removed.

FIG. 37 is a perspective view of a man-portable, control and powersupply assembly to be connected to a hand-held ultrasonic cutting pendevice in accordance with an exemplary embodiment of the presentinvention.

FIG. 38 is a different perspective view of the man-portable, control andpower supply assembly of FIG. 37.

FIG. 39 is a side elevational view of an exemplary handle with theleft-side and upper shell removed to show awaveguide-movement-generation assembly and a smart battery in accordancewith an exemplary embodiment of the present invention.

FIG. 40 is a perspective view of a left side of an ultrasonic cuttingdevice handle with fully integrated control, drive and matchingcomponents, and transducer in a removable module, a removable batterypack, control buttons, and a display screen in accordance with anexemplary embodiment of the present invention.

FIG. 41 is a perspective rear view of view of the exemplary handle ofFIG. 13 with the transducer removed in accordance with an exemplaryembodiment of the present invention.

FIG. 42 is a perspective view of the exemplary handle of FIG. 23 withthe waveguide-movement-generation assembly removed in accordance with anexemplary embodiment of the present invention.

FIG. 43 is a perspective cutaway view of the exemplary removedwaveguide-movement-generation assembly of FIG. 43 in accordance with anexemplary embodiment of the present invention.

FIG. 44 is a side elevational cutaway view of the exemplary handle ofFIG. 25 with the left-side shell removed to show connection detailsbetween the waveguide and waveguide-movement-generation assembly inaccordance with an exemplary embodiment of the present invention.

FIG. 45 is a rear perspective view of the SCUD of FIG. 22 with a displayincluded on the waveguide-movement-generation assembly and a see-throughwindow on the waveguide-movement-generation assembly access doorallowing viewing of the display and in accordance with an exemplaryembodiment of the present invention.

FIG. 46 is a side elevational view of an exemplary handle with theright-side shell removed to show an ultrasonic waveguide drivingassembly having integrated power source, power source control circuit,and ultrasonic waveform-generating circuit in accordance with anexemplary embodiment of the present invention.

FIG. 47 is a side elevational view of an exemplary ultrasonic surgicalassembly with the left-side shell removed to show a separatelyinsertable and rotatable transducer with an exposed portion inaccordance with an exemplary embodiment of the present invention.

FIG. 48 is a perspective view of the ultrasonic surgical assembly ofFIG. 47.

FIG. 49 is a perspective view of the fully assembled ultrasonic surgicalassembly of FIGS. 47 and 48.

FIG. 50 is a side elevational view of an exemplary ultrasonic surgicalassembly with the left-side shell removed to show a rotatable transducerwith an exposed portion in accordance with an exemplary embodiment ofthe present invention.

FIG. 51 is a process flow diagram showing a method for assembling anultrasonic surgical assembly with a separateultrasonic-signal-generation assembly and transducer in accordance withan exemplary embodiment of the present invention.

FIG. 52 is a process flow diagram showing a method for assembling anultrasonic surgical assembly with an ultrasonic-movement-generationassembly that includes an ultrasonic-signal-generation assembly and atransducer in accordance with an exemplary embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

It is to be understood that the disclosed embodiments are merelyexemplary of the invention, which can be embodied in various forms.Therefore, specific structural and functional details disclosed hereinare not to be interpreted as limiting, but merely as a basis for theclaims and as a representative basis for teaching one skilled in the artto variously employ the present invention in virtually any appropriatelydetailed structure. Further, the terms and phrases used herein are notintended to be limiting; but rather, to provide an understandabledescription of the invention.

Before the present invention is disclosed and described, it is to beunderstood that the terminology used herein is for the purpose ofdescribing particular embodiments only and is not intended to belimiting. In this document, the terms “a” or “an”, as used herein, aredefined as one or more than one. The term “plurality,” as used herein,is defined as two or more than two. The term “another,” as used herein,is defined as at least a second or more. The terms “including” and/or“having,” as used herein, are defined as comprising (i.e., openlanguage). The term “coupled,” as used herein, is defined as connected,although not necessarily directly, and not necessarily mechanically.Relational terms such as first and second, top and bottom, and the likemay be used solely to distinguish one entity or action from anotherentity or action without necessarily requiring or implying any actualsuch relationship or order between such entities or actions. The terms“comprises,” “comprising,” or any other variation thereof are intendedto cover a non-exclusive inclusion, such that a process, method,article, or apparatus that comprises a list of elements does not includeonly those elements but may include other elements not expressly listedor inherent to such process, method, article, or apparatus. An elementproceeded by “comprises . . . a” does not, without more constraints,preclude the existence of additional identical elements in the process,method, article, or apparatus that comprises the element.

As used herein, the term “about” or “approximately” applies to allnumeric values, whether or not explicitly indicated. These termsgenerally refer to a range of numbers that one of skill in the art wouldconsider equivalent to the recited values (i.e., having the samefunction or result). In many instances these terms may include numbersthat are rounded to the nearest significant figure. In this document,the term “longitudinal” should be understood to mean in a directioncorresponding to an elongated direction of the object being described.

It will be appreciated that embodiments of the invention describedherein may be comprised of one or more conventional processors andunique stored program instructions that control the one or moreprocessors to implement, in conjunction with certain non-processorcircuits and other elements, some, most, or all of the functions ofultrasonic cutting devices described herein. The non-processor circuitsmay include, but are not limited to, signal drivers, clock circuits,power source circuits, and user input and output elements.Alternatively, some or all functions could be implemented by a statemachine that has no stored program instructions, or in one or moreapplication specific integrated circuits (ASICs), in which each functionor some combinations of certain of the functions are implemented ascustom logic. Of course, a combination of the two approaches could alsobe used. Thus, methods and means for these functions have been describedherein.

The terms “program,” “software application,” and the like as usedherein, are defined as a sequence of instructions designed for executionon a computer system. A “program,” “computer program,” or “softwareapplication” may include a subroutine, a function, a procedure, anobject method, an object implementation, an executable application, anapplet, a servlet, a source code, an object code, a sharedlibrary/dynamic load library and/or other sequence of instructionsdesigned for execution on a computer system.

The present invention, according to one embodiment, overcomes problemswith the prior art by providing a lightweight, hand-holdable, ultrasoniccutting device that is powered by and controlled with components thatfit entirely within a handle of the device. The hand-held device allowsa surgeon to perform ultrasonic cutting and/or cauterizing in anysurgical procedure without the need for external power and,particularly, without the presence of cords tethering the surgeon to astationary object and constricting the ability of the surgeon whileperforming the surgical procedure.

The embodiments of the present invention, unlike the prior art devices,monitor and control motional parameters of the blade-moving transducer.By monitoring motional parameters, as opposed to simple current orvoltage inputs, as is done in the prior art, the amount of cuttingmovement of the blade is maintained throughout a variety of materialsand corresponding loads placed on the blade.

Ultrasonic Surgical Device

Described now is an exemplary apparatus according to one embodiment ofthe present invention. Referring to FIG. 3, a block circuit diagramshows the invention 300, which includes a microprocessor 302, a clock330, a memory 326, a power supply 304 (e.g., a battery), a switch 306(e.g., a MOSFET power switch), a drive circuit 308 (PLL), a transformer310, a signal smoothing circuit 312 (also referred to as a matchingcircuit and can be, e.g., a tank circuit), a sensing circuit 314, atransducer 316, and a waveguide, which terminates into an ultrasoniccutting blade 318, referred to herein simply as the waveguide 318. Theinvention also includes a cannula 320 for covering and supporting thewaveguide 318. As used herein, the “waveguide-movement-generationassembly” is a sub-assembly including at least the transducer 316, butcan also include other components, such as the drive circuit 308 (PLL),transformer 310, signal smoothing circuit 312, and/or the sensingcircuit 314.

Ultrasonic cutting blades and waveguides are known in the art. Thepresent invention's ability to provide all of the necessary componentsof an ultrasonic cutting tool in a hand-held package provides a greatadvantage over prior-art devices, which house a majority of the devicecomponents within a very expensive and heavy desktop box 202, as shownin FIG. 2, and create an expensive and bulky tether 208 between thedevice's handpiece 112 and the box 202.

One feature of the present invention that severs the dependency on highvoltage (120 VAC) input power (a characteristic of all prior-artultrasonic cutting devices) is the utilization of low-voltage switchingthroughout the wave-forming process and amplification of the drivingsignal only directly before the transformer stage. For this reason, inone exemplary embodiment of the present invention, power is derived fromonly a battery, or a group of batteries, small enough to fit eitherwithin the handpiece 112 or within a small box that attaches to theuser, for example, at a waistband. State-of-the-art battery technologyprovides powerful batteries of a few centimeters in height and width anda few millimeters in depth. By combining the features of the presentinvention to provide an entirely self-contained and self-poweredultrasonic device, the capital outlay of the countertop box 202 iseliminated—resulting in almost a ten-fold reduction of manufacturingcost.

The output of the battery 304 is fed to and powers the processor 302.The processor 302 receives and outputs signals and, as will be describedbelow, functions according to custom logic or in accordance withcomputer programs that are executed by the processor 302. The device 300can also include a main memory 326, preferably, random access memory(RAM), that stores computer-readable instructions and data.

The output of the battery 304 also goes to a switch 306 that has a dutycycle controlled by the processor 302. By controlling the on-time forthe switch 306, the processor 302 is able to dictate the total amount ofpower that is ultimately delivered to the transducer 316. In oneembodiment, the switch 306 is an electrically controlledmetal-oxide-semiconductor field-effect transistor (MOSFET), althoughother switches and switching configurations are adaptable as well. Theoutput of the switch 306 is fed to a drive circuit 308 that contains,for example, a phase detecting PLL and/or a low-pass filter and/or avoltage-controlled oscillator. The output of the switch 306 is sampledby the processor 302 to determine the voltage and current of the outputsignal (referred to in FIG. 3 respectively as AD2 V In and AD3 I In).These values are used in a feedback architecture to adjust the pulsewidth modulation of the switch 306. For instance, the duty cycle of theswitch 306 can vary from about 20% to about 80%, depending on thedesired and actual output from the switch 306.

The drive circuit 308, which receives the signal from the switch 306,includes an oscillatory circuit that turns the output of the switch 306into an electrical signal having a single ultrasonic frequency, e.g., 55kHz (referred to as VCO in FIG. 3). As will be explained below, asmoothed-out version of this ultrasonic waveform is ultimately fed tothe transducer 316 to produce a resonant sine wave along the waveguide318. Resonance is achieved when current and voltage are substantially inphase at the input of the transducer 316. For this reason, the drivecircuit 308 uses a PLL to sense the current and voltage input to thetransducer 316 and to synchronize the current and voltage with oneanother. This sensing is performed over line 328. However, unlikeprior-art devices that simply match the phase of the input current tothe phase of the input voltage, the present invention utilizes theinventive concept of matching the current phase with a phase of the“motional” voltage and/or matches the input voltage phase with a phaseof the “motional” current. The concept and technique of measuringmotional voltage will be explained in detail below and in conjunctionwith the figures.

At the output of the drive circuit 308 is a transformer 310 able to stepup the low voltage signal(s) to a higher voltage. It is noted that allupstream switching, prior to the transformer 310, has been performed atlow (i.e., battery driven) voltages, something that, to date, has notbeen possible for ultrasonic cutting and cautery devices. This is atleast partially due to the fact that the drive circuit 308advantageously uses low on-resistance MOSFET switching devices. Lowon-resistance MOSFET switches are advantageous, as they produce lessheat than traditional MOSFET device and allow higher current to passthrough. Therefore, the switching stage (pre transformer) can becharacterized as low voltage/high current.

In one embodiment of the present invention, the transformer 310 steps upthe battery voltage to 120V RMS. Transformers are known in the art andare, therefore, not explained here in detail. The output of thetransformer 310 resembles a square wave 400, an example of which isshown in FIG. 4, which waveform is undesirable because it is injuriousto certain components, in particular, to the transducer 316. The squarewave also generates interference between components. The matchingcircuit 312 of the present invention substantially reduces or eliminatesthese problems.

The wave shaping or matching circuit 312, sometimes referred to as a“tank circuit,” smoothes the square wave 400 output from the transformer310 and turns it into a driving wave 500 (e.g., a sine wave) anapproximation of which is shown in FIG. 5. The matching circuit 312, inone embodiment of the present invention, is a series L-C circuit and iscontrolled by the well-known principles of Kirchhoff's circuit laws.However, any matching circuit can be used here. The smooth sine wave 500output from the matching circuit 312 is, then, fed to the transducer316. Of course, other driving signals can be output from the matchingcircuit 312 that are not smooth sine waves.

A transducer 316 is an electro-mechanical device that convertselectrical signals to physical movement. In a broader sense, atransducer is sometimes defined as any device that converts a signalfrom one form to another. An analogous transducer device is an audiospeaker, which converts electrical voltage variations representing musicor speech to mechanical cone vibration. The speaker cone, in turn,vibrates air molecules to create acoustical energy. In the presentinvention, the driving wave 500 is input to the transducer 316, whichthen imparts physical movements to the waveguide 318. As will be shown,this movement sets up a resonating wave on the waveguide 318, resultingin motion at the end of the waveguide 318.

FIG. 6 provides a diagrammatic illustration of the effect that aresonant sine wave input to a transducer has on a waveguide of theultrasonic cutting device in accordance with an exemplary embodiment ofthe present invention with the sinusoidal pattern shown representing theamplitude of axial motion along the length of the waveguide. As can beseen in FIG. 6, the transducer 316 is coupled to the waveguide 318.Responding to a positive portion 502 of the driving sine wave 500, thetransducer 316 moves a portion 604 of the transducer 316, which isphysically attached to a portion 606 of the attached waveguide 318, in afirst direction 608. Likewise, the transducer 316 responds to a negativeportion 504 of the driving wave 500 and moves the portion 604 of thetransducer 316 in a second direction 612. A smooth sine wave 500, incontrast to the square wave 400, allows the transducer 316 and waveguide318 to slow before changing directions. The smoother movement is lessinjurious to the device's components. One exemplary embodiment of theportion 604 is a stack of piezo-electric crystals.

The alternating movement 608, 612 of the transducer portion 604 places asinusoidal wave 614 along the length of the waveguide 318. The wave 614alternatively pulls the end 620 of the waveguide 318 toward thetransducer 316 and pushes it away from the transducer 316, therebylongitudinally moving the tip 620 of the waveguide 318 along distance618. The tip is considered an “anti-node,” as it is a moving point ofthe sine wave 614. The resulting movement of the waveguide 318 producesa “sawing” movement along distance 618 at the end of the waveguide 318.(The wave 614 and linear movement along distance 618 are greatlyexaggerated in FIG. 6 for ease of discussion.) This high-speed movementalong distance 618, as is known in the art, provides a cutting waveguidethat is able to slice easily through many materials, such as tissue andbone. The waveguide 318 also generates a great deal of frictional heatwhen so stimulated, which heat is conducted within the tissue that thewaveguide 318 is cutting. This heat is sufficient to cauterize instantlyblood vessels within the tissue being cut.

If the driving wave 614 traveling along the waveguide 318 is not aresonant wave, the last anti-node of the wave 614 will not appear at thetip 620 of the waveguide 318. In such a case, the tip 620 of thewaveguide 318 may move transverse to the longitudinal axis of thewaveguide 318, creating an incorrect mode, e.g. the tip 620 not moving,a slapping motion with the tip 620, or several others. This incorrectmode is not ideal and is not reliable for providing adequate cutting andsurgical cautery. The invention, however, utilizes the PLL in the drivecircuit 308 to ensure that the movement 608, 612 of the waveguide 318remains resonant along the waveguide 318 by monitoring the phase betweenthe motional current and motional voltage waveforms fed to thetransducer 316 and sending a correction signal back to the drive circuit308. As an added feature, the present invention can be provided withpiezo-electric crystal stacks 604 that are cut in a different plane,thereby creating a torsional, or twisting motion of the blade ratherthan only a sawing motion. The present invention can easily be adaptedto a full set of uses using requiring a drilling-type motion instead ofor with the sawing motion just described.

Transducer Circuit Model

FIG. 7 is a schematic circuit diagram of a model transducer 700, such astransducer 316, which contains piezo-electric material. Piezo-electrictransducers are well known in the art. The mass and stiffness of thepiezo-electric material creates a mechanically resonant structure withinthe transducer. Due to the piezo-electric affect, these mechanicalproperties manifest themselves as electrically equivalent properties. Inother words, the electrical resonant frequency seen at the electricalterminals is equal to the mechanical resonant frequency. As shown inFIG. 7, the mechanical mass, stiffness, and damping of the transducer316 may be represented by a series configuration of an inductor/coil L,a capacitor C₂, and a resistor R, all in parallel with another capacitorC₁. The electrical equivalent transducer model 700 is quite similar tothe well-known model for a crystal.

Flowing into an input 710 of the electrical equivalent transducer model700 is a transducer current i_(T). A portion i_(C) of i_(T) flows acrossthe parallel capacitor C_(I), which is of a selected type and valuethat, for the majority of the expected frequency range, retains asubstantially static capacitive value. The remainder of i_(T), which isdefined as i_(M) is simply i_(T)−i_(C) and is the actual workingcurrent. This remainder current i_(M) is referred to herein as the“motional” current. That is, the motional current is that currentactually performing the work to move the waveguide 318.

Known prior-art designs regulate and synchronize with the total currenti_(T), which includes i_(C) and is not an indicator of the actual amountof current actually causing the motion of the waveguide 318 of thetransducer 316. For instance, when the blade of a prior-art device movesfrom soft tissue, to more dense material, such as other tissue or bone,the resistance R increases greatly. This increase in resistance R causesless current i_(M) to flow through the series configuration R-L-C₂, andmore current i_(C) to flow across capacitive element C₁. In such a case,the waveguide 318 slows down, degrading its performance. It may beunderstood by those skilled in the art that regulating the overallcurrent is not an effective way to maintain a constant waveguide speed.As such, one novel embodiment of the present invention advantageouslymonitors and regulates the motional current i_(M) flowing through thetransducer 316. By regulating the motional current i_(M), the movementdistance of the waveguide 318 can be regulated easily.

Surgical Device Circuit Model

FIG. 8 is a schematic circuit diagram of an inventive circuit 800 usefulfor understanding how to obtain the motional current i_(M) of atransducer 700. The circuit 800 has all of the circuit elements of thetransducer 700 plus an additional bridging capacitive element C_(B) inparallel with the transducer 700 of FIG. 7. However, the value of C_(B)is selected so that C₁/C_(B) is equal to a given ratio r. Forefficiency, the chosen value for C_(B) should be relatively low. Thislimits the current that is diverted from i_(M). A variable power sourceV_(T) is applied across the terminals 802 and 804 of the circuit 800,creating a current i_(B) through the capacitive element C_(B), a currenti_(T) flowing into the transducer 700, a current i_(C) flowing throughcapacitor C₁, and, finally, the motional current i_(M). It then followsthat i_(M)=i_(T)−r·i_(B). This is because:

$i_{B} = {{C_{B} \cdot \frac{\partial V_{T}}{\partial_{t}}} = {{{\frac{C_{1}}{r} \cdot \frac{\partial V_{T}}{\partial_{t}}}\mspace{14mu} {and}\mspace{14mu} i_{C}} = {C_{1} \cdot \frac{\partial V_{T}}{\partial_{t}}}}}$

Therefore, i_(C)=r·i_(B) and, substituting for i_(C) in the equationi_(M)=i_(T)−i_(C), leads to: i_(m)=i_(T)−r·i_(B).

Now, by knowing only the total current and measuring the current throughthe bridge capacitor i_(B), variations of the transducer's motionalcurrent i_(M) can be identified and regulated. The driver circuit 308,then, acts as a current controller and regulates the motional currenti_(M) by varying an output of the transformer 310 based on the productof the current flowing through the bridge capacitance C_(B) multipliedby the ratio r subtracted from a total current i_(T) flowing into thetransducer 700. This regulation maintains a substantially constant rateof movement of the cutting blade portion of the waveguide 318 across avariety of cutting loads—something that has not been possible to date.In one embodiment, the sensing circuits 314 measure the motional voltageand/or motional current. Current and voltage measuring devices andcircuit configurations for creating voltage meters and current metersare well known in the art. Values of current and voltage can bedetermined by the present invention in any way now known or laterdeveloped, without limitation.

Regulation of the motional current i_(M) is a true way to maintain theintegrity of the instrument and ensure that it will operate at its peakperformance under substantially all conditions expected in an operatingenvironment. In addition, such regulation provides these advantageswithin a package small enough and light enough to be easily held in onehand—a configuration that has never occurred in the field.

Transducer Circuit Model

FIG. 9 shows another embodiment of the present invention, where thetransducer 316 is schematically represented as a parallel configurationof a resistive element R, an inductive element L, and a capacitiveelement C₄. An additional capacitive element C₃ is in a seriesconfiguration between an input 802 and the parallel configuration of theresistive element R, the inductive element L, and the capacitive elementC₄. This parallel representation models the action of the transducer inthe “antiresonant” mode of operation, which occurs at a slightlydifferent frequency. A transducer voltage V_(T) is applied between theinput terminals 802, 804 of the transducer 316. The transducer voltageV_(T) is split between a voltage V_(C) across capacitive element C₃ anda motional voltage V_(M) across the parallel configuration of theresistive element R, the inductive element L, and the capacitive elementC₄. It is the motional voltage V_(M) that performs the work and causesthe waveguide 318 to move. Therefore, in this exemplary embodiment, itis the motional voltage that should be carefully regulated.

Surgical Device Circuit Model

FIG. 10 shows an exemplary embodiment of an inventive circuitconfiguration 1000, according to the present invention. The circuitconfiguration 1000 includes the transducer 900 of FIG. 9 and adds to itthree additional capacitive elements C₅, C₆, and C₇. Capacitive elementC₅ is in series with the transducer circuit 900 of FIG. 9 while thecapacitive elements C₆ and C₇ are in series with one another and,together, are in parallel with the series combination of the capacitiveelement C₅ and the transducer circuit 900.

This circuit is analogous to a Wheatstone bridge measuring instrument.Wheatstone bridge circuits are used to measure an unknown electricalresistance by balancing two legs of a bridge circuit, one leg of whichincludes the unknown component. In the instant circuit configurationshown in FIG. 10, a motional voltage V_(M), which equals V_(T)−V_(C), isthe unknown. By determining and regulating the motional voltage V_(M),the inventive configuration allows a consistent waveguide movement to bemaintained as set forth below.

Advantageously, the capacitive element C₇ is selected so that its valueis a ratio A of capacitive element C₃, with A being less than one.Likewise, the capacitive element C₆ is selected so that its value is thesame ratio A of the capacitive element C₅. The ratio of C₅/C₃ is alsothe ratio A.

Because the ratio of C₃/C₇ is A and the ratio of C₅/C₆ is also A, thebridge is balanced. It then follows that the feedback voltage V_(fb),divided by the motional voltage V_(M), is also the ratio A. Therefore,V_(m) can be represented as simply A·V_(fb).

If the voltage across the transducer 900 is still V_(T), an inputvoltage V_(in) equals V_(T) plus the voltage V_(B) across the capacitiveelement C₅. The feedback voltage V_(FB) is measured from a first pointlocated between capacitive elements C₆ and C₇ and a second point locatedbetween the transducer and the capacitive element C₅. Now, the upstreamcomponents of the circuit 300 act as a voltage controller and vary thepower V_(in) to maintain a constant feedback voltage V_(fb), resultingin a substantially constant motional voltage and maintaining asubstantially constant rate of movement of the cutting blade portion ofthe waveguide 318 across a variety of cutting loads. Again, unlike theprior art, the present invention is not simply regulating the inputvoltage V_(in), it is varying the input voltage V_(in) for the purposeof regulating the motional voltage V_(M)—which is novel in the art.

FIG. 11 shows another embodiment of the present invention where thetransducer 700 is of the circuit configuration shown in FIG. 7. Theconfiguration of FIG. 11 works similarly to that shown in FIG. 8 and asdescribed above in connection with FIG. 8. However, in this circuitconfiguration 1100, a pair of transformers 1104 and 1108 is used todetermine and monitor the motional voltage V_(M). In this embodiment, aprimary winding 1102 of the first transformer 1104 is in a seriesconfiguration with a bridge capacitor C_(B). Similarly, a primarywinding 1106 of the second transformer 1108 is in a series configurationwith the transducer 700. The leads 1110 and 1112 of the secondarywinding 1114 of the first transformer 1104 are coupled through aresistor R₂. The leads 1116 and 1118 of the secondary winding 1120 ofthe second transformer 1108 are coupled through a resistor R₁. Inaddition, the first lead 1110 of the secondary winding 1114 of the firsttransformer 1104 is directly connected to the first lead 1116 of thesecondary winding 1120 of the second transformer 1108.

Current i_(B) passing through the primary winding 1102 of the firsttransformer 1104 induces a current in the secondary winding 1114 of thefirst transformer 1104. Similarly, the currents including i_(C) passingthrough the capacitive element C₁ of the transducer 700 and the motionalcurrent i_(M) of the transducer 700 combine and go through the primarywinding 1106 of the second transformer 1108 to find ground 1122. Thecurrent in the primary winding 1106 induces a current on the secondarywinding 1120. As noted by the dots (“•”) on the transformers 1104, 1108,the secondary windings 1114 and 1120 are in opposite directions from oneanother, with reference to the primary windings 1102, 1106,respectively, and induce a voltage V_(fb) across resistors R₁ and R₂. Byselecting values for R₁ and R₂ so that a ratio of R₁/R₂ is equal to theratio of the values C_(B)/C₁, the feedback voltage V_(fb) will always beproportional to the motional current i_(M). Now, the upstream componentsof the circuit 300 (see FIG. 3) act as a voltage controller and vary theinput power (V_(in) and I_(T)) to maintain a constant feedback voltageV_(fb), resulting in a substantially constant motional current i_(M) andmaintaining a substantially constant rate of movement of the cuttingblade portion of the waveguide 318 across a variety of cutting loads.Again, unlike the prior art, the present invention is not simplyregulating the input voltage V_(in), it is varying the input currentI_(T) for the purpose of regulating the motional current i_(M)—which isnovel in the art.

FIG. 12 shows another embodiment of the present invention where thetransducer 900 is modeled by the circuit configuration shown in FIG. 9.The configuration of FIG. 12 works similarly to that shown in FIG. 10and as described above in connection with FIG. 10. However, in thiscircuit configuration 1200, a transformer 1210 is used to determine andmonitor the motional voltage V_(M) of the transducer 900. In thisembodiment, a primary winding 1206 of the transformer 1210 is in aseries circuit configuration with an inductive element L₂ and acapacitive element C₁. A voltage V_(in) is applied across input leads1202 and 1204 of the circuit formed by the primary winding 1206 of thetransformer 1210, the inductive element L₂, and the capacitive elementC₁. A current through the primary winding 1206 induces a correspondingcurrent in the secondary winding 1208 of the transformer 1210. Thesecondary winding 1208 of the transformer 1210 is in a parallelconfiguration with a combination of the transducer 900 and a bridgecapacitor C_(B). The two components forming the combination are in aseries configuration.

In this embodiment, the secondary winding 1208 is tapped at a point1212. By tapping the secondary winding 1208 at a point where a firstportion of the secondary winding 1208 has m turns and a second portionof the secondary winding 1208 has n turns (where n is less than m), aselectable percentage of the induced voltage on the secondary winding1208 appears from point 1212 to ground 1214.

Again, this circuit is analogous to a Wheatstone bridge measuringinstrument. One leg is the first secondary winding in, the second leg isthe second secondary winding n, the third leg is the transducer 900, andthe fourth leg is the capacitor C_(B). In the instant circuitconfiguration shown in FIG. 12, the voltage V_(M) is the unknown. Bydetermining and regulating the motional voltage V_(M), a consistentwaveguide movement is maintained.

By selecting a value of the bridge capacitor C_(B) to be less than thetransducer capacitance C₃ by the same percentage that the number ofturns n is less than the number of turns m (i.e., m/n=C₃/C_(B)), thevalue of a feedback voltage V_(fb) will reflect the motional voltageV_(M). The invention can determine whether the motional voltage V_(M) ischanging by monitoring the feedback voltage V_(fb) for changes.

By using the equivalent-circuit transducer model 900, which models aparallel-resonant (or “anti-resonant”) transducer, the transducer may bedriven in the parallel resonant mode of operation, where motion isproportional to voltage. The advantage of this mode of operation is thatthe required constant-voltage-mode power supply is simpler to design andsafer to operate than a constant-current-mode power supply. Also,because the transducer has a higher impedance when unloaded (rather thana lower impedance when unloaded in the series-resonant mode ofoperation), it naturally tends to draw less power when unloaded. Theparallel-resonant mode of operation, however, is more difficult tomaintain because the resonant bandwidth is narrower than that of theseries-resonant mode and it has a slightly different natural resonantfrequency; hence, the mechanical components of the device must bespecifically configured to operate at either the series resonant orparallel-resonant mode of operation.

Now, the upstream components of the circuit 300 act as a voltagecontroller and vary the power V_(in) to maintain a constant feedbackvoltage V_(fb), resulting in a substantially constant motional voltageV_(M) and maintaining a substantially constant rate of movement of thecutting blade portion of the waveguide 318 across a variety of cuttingloads. Again, unlike the prior art, the present invention is not simplyregulating the input voltage V_(in), it is varying the input voltageV_(in) for the purpose of regulating the motional voltage V_(M)—which isnovel in the art.

In each of the circuit configurations described and shown in FIGS. 7-12,circuit component degradation can impact negatively the entire circuit'sperformance. One factor that directly affects component performance isheat. Known circuits generally monitor switching temperatures (e.g.,MOSFET temperatures) However, because of the technological advancementsin MOSFET designs, and the corresponding reduction in size, MOSFETtemperatures are no longer a valid indicator of circuit loads and heat.For this reason, the present invention senses with the sensing circuit314 the temperature of the transformer 310 according to an exemplaryembodiment. This temperature sensing is very advantageous as transformer310 is run at or very close to its maximum temperature during use of thedevice. Additional temperature will cause the core material, e.g., theferrite, to break down and permanent damage can occur. The presentinvention can respond to a maximum temperature of the transformer 310by, for example, reducing the driving power in the transformer 310,signaling the user, turning the power off completely, pulsing the power,or other appropriate responses.

Referring back to FIG. 1, in one embodiment, the processor 302 iscommunicatively coupled to the clamping mechanism 118, which is used toplace material in physical contact with the blade portion of thewaveguide 318. The clamping mechanism 118 has a range of clamping forcevalues and the processor 302 varies the motional voltage V_(M) basedupon the received clamping force value. Because high force valuescombined with a set motional rate can result in high blade temperatures,a temperature sensor 322 can be communicatively coupled to the processor302, where the processor 302 is operable to receive and interpret asignal indicating a current temperature of the blade from thetemperature sensor 322 and determine a target frequency of blademovement based upon the received temperature.

According to an embodiment of the present invention, the PLL 308, whichis coupled to the processor 302, is able to determine a frequency ofwaveguide (318) movement and communicate the frequency to the processor302. The processor 302 stores this frequency value in the memory 326when the device is turned off. By reading the clock 330, the processor302 is able to determine an elapsed time after the device is shut offand retrieve the last frequency of waveguide movement if the elapsedtime is less than a predetermined value. The device can then start up atthe last frequency, which, presumably, is the optimum frequency for thecurrent load.

Transducer

FIGS. 13 to 30 show various exemplary embodiments of a “gun” type device1300, 1800, 2300 suitable to hold and/or contain the entire inventivedevice illustrated in the diagram of FIG. 3. More specifically, as shownin the cutaway view of FIG. 14, the ultrasonic surgical device 1300includes a disposable ultrasonic cutting tool handle 1408 that has awater-tight sealable battery-holding compartment 1422, a driving-wavegeneration circuit 1420 in electrical contact with the battery-holdingcompartment 1422, a transducer attachment dock 1404 accessible from anexterior of the handle and operable to releasably physically couple thetransducer 1302 to a waveguide 1310 (represented as a dotted line inFIG. 13) coupled to the handle 1408 through a waveguide attachment dock1406 that is disposed to accept and physically couple the ultrasonicwaveguide 1310 to the transducer 1302.

The ultrasonic surgical device 1300 includes a disposable handle body1308 defining a battery-holding compartment 1422 shaped to receive abattery 1700 therein and operable to couple a proximal end of theultrasonic waveguide 1310 to the ultrasonic transducer 1302therethrough. The handle body 1308 has a transducer dock 4102 (shownbest in FIG. 41) exposed to the environment and shaped tointerchangeably house at least a portion of the transducer 1302 thereat.The handle body 1308 further includes a waveguide attachment dock 1428shaped to align and attach the proximal end of the waveguide 1310 to thetransducer 1302 and thereby hold the waveguide 1310 and the transducer1302 at least partially within the body when the transducer 1302 isdocked in the transducer dock 4102 and the waveguide 1310 is docked inthe waveguide attachment dock 1428.

An upper portion of the handle body 1308 houses a disposabledriving-wave generation circuit 1420 that is in electrical contact withthe battery 1700 and the transducer 1302 when the battery 1700 andtransducer are disposed, respectively, in the battery-holdingcompartment 1422 and the transducer dock 4102. The generation circuit1420 is operable to generate an output waveform sufficient to generateultrasonic movement along the waveguide by exciting the transducer whenthe transducer is coupled to the waveguide 1310.

The transducer 1302 is generally secured by screwing the transducer 1302onto a waveguide 1310, both being at least partially within thetransducer port 1404. The physical couple between the handle 1408 andthe transducer 1302, once attached, can be water-tight and, in someembodiments, can be aseptic. As explained above, the transducer 1302imparts the physical forces to the waveguide 318 at the proper frequencyand force and receives power from the battery 1700 through conductivepower leads 1426. The transducer assembly 1302 is shown in greaterdetail in FIGS. 15 and 16.

Referring to FIG. 15, the reusable cordless transducer assembly 1402 isshown separate from the device 1300. The inventive transducer assembly1402 includes a shaft 1504 with an ultrasonic waveguide couple 1508 thatis able to attach to a waveguide and, upon activation of the transducershaft 1504, excite the attached waveguide, i.e., impart ultrasonic wavesalong the length of the waveguide. The transducer assembly 1402 also hasa housing 1506 that protects and seals the internal working components(shown in FIG. 16) from the environment. It is advantageous for thetransducer assembly 1402 to be selectively removable from the device1300. As a separate component, the transducer assembly 1402 can bemedically disinfected or sterilized, e.g., put in an autoclave, and usedfor multiple surgeries, while the less-expensive gun itself may bedisposable. In addition, the transducer assembly 1402 can be used inmultiple guns or in the same gun up to a desired maximum number of timesbefore it is required to be disposed.

FIG. 16 shows one exemplary embodiment of the transducer assembly 1302.Within the housing 1506 is the movable shaft 1504. When an electricfield is created in the piezoelectric crystal stack 1604 at one end 1606of the shaft 1504, the shaft 1504 moves laterally within and relative tothe housing 1506. In this embodiment, the waveguide coupler 1508 is maleand includes threads 1610, which are used to secure the transducerassembly 1302 to the non-illustrated waveguide 318 by screwing thewaveguide 318 onto the threads 1610 with an appropriate amount oftorque. In contrast, in FIG. 15, the waveguide coupler 1508 was femaleallowing the waveguide to be screwed into the waveguide coupler 1508.

A novel feature of the transducer 1402 is its ability to mechanicallyand electrically connect at the same time. FIG. 15 shows an exemplaryembodiment of electrical connector rings 1510 of the transducer 1402. Asthe transducer 1402 is being coupled by the waveguide couple 1508 to awaveguide attached to the handle 1408, the connector rings 1510 arebrought into contact with, for example, a set of power contacts 4104,shown in FIG. 41. The power contacts 4104 places the piezoelectriccrystal stack 1604 in contact with the power source 1700 of the handle1408. This substantially simultaneous coupling can be configured tooccur in all embodiments of the present invention.

The transducer assembly 1302 and the transducer assembly housing 1404can be sealed so that, in the rare event of surgical fluids contactingthe transducer assembly 1302, they will not introduce themselves intothe interior of the housing 1506.

The gun 1300, according to an exemplary embodiment of the presentinvention, has, within its handle 1408, a power assembly 1700 (includingpower source 1702 and a generator 1704), referred to herein as abattery-and-generator assembly or “BAG” 1700, shown in detail in FIG.17. The battery 1702 within the BAG 1700 can be a single battery or aplurality of battery cells operating as a unit. Both batteryconfigurations (single or multiple cells) will be referred to herein asthe “battery” 1702 herein.

The battery 1702 powers the generator 1704, which can include some orall of the components shown in FIG. 3 and described in detail above.Specifically, the generator 1704 powers the transducer and includes theprocessor 302, the switch 306 (e.g., a MOSFET power switch), the drivecircuit 308 (PLL), the transformer 310, the signal smoothing/matchingcircuit 312, and the sensing circuit 314. The present invention'sability to provide all of the necessary reusable generator components ofthe ultrasonic cutting tool within the disposable handle 1408 of thegun-type device 1300 provides a great advantage over prior-art devices,which house a majority of the device components within the veryexpensive and heavy desktop box 202 shown in FIG. 2 and which alsocreates an expensive and bulky tether 208 between the device (FIGS. 1and 2) and the box 202. The inventive circuit techniques of the presentinvention sever the dependency on high voltage (120 VAC) input power, acharacteristic of all prior-art ultrasonic cutting devices, and utilizesonly low-voltage switching throughout the wave-forming process.

In addition to the advantages of reduced cost, reduced size, eliminationof a tethering cord for supplying power and carrying signals, and aconstant motional voltage, the instant invention provides uniqueadvantages for maintaining a sterile environment in an operating orother environment. More specifically, in exemplary embodiments of thepresent invention, the handle includes an aseptic seal. An “aseptic”seal, as used herein, means a seal that sufficiently isolates acompartment (e.g., inside the handle) and components disposed thereinfrom a sterile field of an operating environment into which the handlehas been introduced so that no contaminants from one side of the sealare able to transfer to the other side of the seal.

As shown in FIG. 14, for example, the handle 1408 is also provided witha closable door 1412, for instance, at its bottom 1401. This provides avariety of possible assemblies. In one assembly, the gun body 1414,which includes the transducer coupling port 1404 and the triggeringmechanisms 1418, is disposable and never used more than for a singlesurgery. This sub-assembly is generally the least expensive of all ofthe components of the device; in some cases, it is 1/100^(th) of thetotal cost of the device. The transducer 1302, which is much moreexpensive and is autoclavable, can be reused multiple times.

An exemplary procedure for use of the device with the BAG 1700 isexplained with regard to FIGS. 13 and 14. To start, a person in thesterile field opens a sealed package containing the new sterile gun body1408 and removes it for use during the operation. The gun body 1408 caneither already include the cannula 320 and waveguide 1310 (indicatedwith a dashed line) or can be coupled to a cannula 320 and waveguide1310 after the package is opened. Next, the sterile (autoclaved)transducer assembly 1302 is inserted into the gun body 1408 andappropriately attached to the waveguide 1310. The surgeon then presentsthe underside of the gun body 1408 (with the door 1412 open) to thecirculating nurse, who drops the BAG 1700 into the grip portion 1424 ofthe gun handle 1408 without contacting the exterior of the gun body1408. Someone in the operating field (e.g., the surgeon) then closes thedoor 1412, thereby securing the non-sterile BAG 1700 within the gun 1300through a sterile seal 1401 and preventing it from contaminating thesterile field. Because the removable BAG 1700 is sealed within thehandle 1408, it is “outside” the sterile field during surgery.

Self-Contained Ultrasonic Device (SCUD)

FIGS. 18 and 19 show yet another embodiment of the present invention inwhich the gun-shaped exterior body 1800 has a different shape thanexterior body 1300 of FIGS. 13 and 14. The exterior body 1800 is shapedwith a larger upper portion 1802. In this case, the generator, battery,and transducer are able to be inserted, either together as an assembly(referred to herein as an “ultrasonic-movement-generation assembly”) oras separate components into a water-tight sealable cordlessultrasonic-movement-generation-assembly-holding compartment 1904 withinthe upper portion 1802 of the exterior body 1800. The interior of thecompartment 1904 remains outside the sterile field during surgery withthe aid of a sterile seal 1801. This insertion is performed through useof, as shown in FIG. 19, a door 1806, 1906 that can be opened andclosed. When closed, the door 1806, 1906 seals the interior of the gun1800 from the exterior environment of the gun 1800 and vice versa.

FIG. 20 shows an embodiment of the ultrasonic-movement-generationassembly 2000 that includes a battery 2002 (in this embodiment, similarto the embodiment of FIG. 17, the battery is a pack of batteries), adriving-wave generation circuit 2004 (i.e., generator), and a transducer2006. The entire device 1900, shown in FIGS. 19, 21, and 22, is referredto herein as a Self-Contained Ultrasonic Device or “SCUD.” Theultrasonic-movement-generation assembly 2000 can be easily insertedwithin the compartment 1904 of the disposable handle body 1800 and thensealed from the environment by the door 1806, 1906. Advantageously, inthis exemplary embodiment, the ultrasonic-movement-generation assembly2000, similar to the power source 1700, shown in FIG. 17, can besterilized, but does not necessarily need to be sterile because it isshielded from the operating environment. This provides a tremendousadvantage over prior art devices because theultrasonic-movement-generation assembly 2000 and BAG 1700 do not have tobe watertight or autoclavable. Without the requirements of beingwatertight and sterilizable, the electrical connectivity of thecomponents can be easily and inexpensively obtained. For instance, whenelectrically connected components must be hermetically, or simplywaterproof-sealed, the contacts need to be securely protected frommoisture and from separation during the high temperature solutions towhich they are exposed. For instance, leads would need to be solderedtogether or otherwise securely affixed to one another and wrapped with aprotective coating to prevent rust/tarnishing and/or separation. Thisprotective requirement is not present or at least not as stringent ifthe components can simply be slipped inside of an outer protectivechamber, such as the handle of the ultrasonic gun 1300, 1800 of thepresent invention. These advantageous features reduce costs andfailures, make troubleshooting much easier, and allow replacing orswitching parts to be relatively simple. For instance, fromtime-to-time, a battery will “go bad” or not function properly. When aunit is fully sealed, opening it to replace the battery with anotherrenders the device no longer hermetically sealed or, at a minimum, nolonger reliably sealed. In contrast to such hermetically sealed devices,when the ultrasonic-movement-generation assembly 2000 (e.g., shown inFIG. 20) is made to be inserted into a sealed chamber, it can beconfigured to open easily and allow any component therein to be removedand exchanged as desired. Including all of the expensive components ofthe system in the reusable ultrasonic-movement-generation assembly 2000allows for a simple and inexpensive design for the disposable ultrasonicgun portion of the system.

FIGS. 21 and 22 show the disposable handle body 1800 with theultrasonic-movement-generation assembly 2000 inserted in the upperchamber 1904. The disposable handle body 1800 has a waveguide attachmentdock 2104 disposed on an exterior of the body 1800, which is exposed tothe environment and has a first couple 2108 operable to releasablyphysically couple a waveguide to the handle body 1800. The upper chamber1904 is a water-tight, aseptically sealable,waveguide-movement-generation-assembly-holding compartment and haswithin its interior a waveguide-movement-generation assembly attachmentdock 2106 that is operable to releasably physically couple theultrasonic-movement-generation assembly 2000 to the handle 2101 andplace the ultrasonic-movement-generation assembly 2000 in directphysical contact with an ultrasonic waveguide. Theultrasonic-movement-generation assembly 2000 is held in place by a door1906 having an open position (shown in FIG. 22) that allows entry of theultrasonic-movement-generation assembly 2000 into the chamber 1904 andremoval of ultrasonic-movement-generation assembly 2000 from the chamber1904. The door 1906 also has a closed position (shown in FIG. 21) thataseptically seals the interior from the exterior of the handle. In oneexemplary embodiment, the chamber 1904 has a motion-generator-assemblyejector 2110 extending at least partially within the holding compartment1904 and operable to activate (e.g., by movement of the door 1906 fromthe closed position to the open position) and at least partially ejectthe assembly 2000 from the holding compartment 1904.

Once inserted, the gun 1800 is fully functional and ready to use with awaveguide (see, e.g., FIG. 25). The exemplary embodiment shown in FIGS.18-22 allows the costliest portions of the gun to be reused as manytimes as desired and, advantageously, the portion of the device that issubject to fluids and other contaminates, i.e., the gun 1800, to be oflow cost and disposed after the surgery.

Another advantage of a removable ultrasonic-movement-generation assembly2000 or the BAG 1700 is realized when lithium-ion (Li) batteries areused. As previously stated herein, lithium batteries should not becharged in a parallel configuration of multiple cells. This is because,as the voltage increases in a particular cell, it begins to accept morecharge faster than the other lower-voltage cells. Therefore, each cellmust be monitored so that a charge to that cell can be controlledindividually. When a lithium battery is formed from a group of cells, amultitude of wires extending from the exterior of the device to thebattery 1702 is needed, at least one additional wire for each batterycell beyond the first. By having a removableultrasonic-movement-generation assembly 2000 or BAG 1700, each batterycell can have its own exposed set of contacts and, when not presentinside the device, each set of contacts can coupled to a correspondingset of contacts in an external, non-sterile battery-charging device.

Transducer-and-Generator Assembly (TAG)

FIGS. 23-30 and 42-45 show yet another exemplary embodiment 2300 of thepresent invention, which includes a disposable ultrasonic cutting toolhandle 2301, a waveguide 2504, 2508, a waveguide-movement-generationassembly 2303, which includes the transducer and driving-wave generationcircuit (generator shown in FIG. 24), and a battery 304. Thisembodiment, for ease of reference, is referred to herein as aTransducer-and-Generator assembly, or “TAG” 2300, which acronym refersto the contents of the removable waveguide-movement-generation assembly2303.

The handle 2301 of the TAG 2300 includes a first handle body portion2302 defining therein an aseptically sealable battery-holdingcompartment 2410 shaped to receive a removable battery 304 therein. Thehandle 2301 further includes a second handle body portion 2310 that isconnected to, or integral with, the first handle body portion 2302. Thesecond handle body portion 2310 has a waveguide attachment dock 2416exposed to the environment and having a first couple 2418 operable toconnect an ultrasonic waveguide 2504, 2508 thereto, as shown in FIG. 25.The handle 2301 also includes an ultrasonic-movement-generation assemblydock 4202 (shown in FIG. 42) exposed to the environment and shaped toconnect the ultrasonic waveguide 2508 in the waveguide attachment dock2418 to an ultrasonic-movement-generation assembly 2303 through thesecond handle body portion 2310. An electrical couple (such as couple4106, shown in FIG. 41), connects the battery 304 within thebattery-holding compartment 2410 to the ultrasonic-movement-generationassembly 2303 when the ultrasonic-movement-generation assembly 2303 isdocked at the ultrasonic-movement-generation assembly dock 4202. As analternative to this exemplary embodiment, the battery 304 can includepart or all of the driving-wave generation circuit.

The removable ultrasonic-movement-generation assembly 2303 is a cordless(i.e., battery powered) assembly and has a selectively removablesecuring connector 4204 and an output couple 4206 operable to impartultrasonic movement to the ultrasonic waveguide 2508 when the waveguide2508 is connected thereto. The assembly 2303 includes a shell 2304,shown in FIG. 23, housing an ultrasonic generator 2404 and an ultrasonictransducer 2406, both shown in FIG. 24. The shell 2304 has a securingconnection 4204 shaped to selectively removably connect to a firstconnector part 4208 of the ultrasonic surgical handle 2300, shown inFIG. 42. The connection 4204 can be a “dove-tail,” as shown in theexemplary embodiment of the figures or any other coupling method thatallows the ultrasonic-movement-generation assembly 2303 to be removablyattached to the handle 2301. The transducer 2406 has an output couple4206 operable to impart ultrasonic movement to an ultrasonic waveguide2508 when the waveguide 2508 is connected thereto. In one embodiment,the output couple 4206 is a threaded connection that can be screwed ontoor into a waveguide 2508. In addition, theultrasonic-movement-generation assembly 2303 can be a sealed watertightand/or autoclavable assembly that can be used in a surgical procedure,sterilized, and then simply be coupled to a brand new handle 2300 toperform a second surgical procedure. As will be described, the TAG 2303can take several different embodiments.

FIG. 24 is a cutaway view showing the interior of the TAG 2300 with thenear-side (left side) cover of the handle 2301 and the shell 2304 of theultrasonic-movement-generation assembly 2303 removed. Here, the powersupply 304 (e.g., a battery) fits entirely within the first portion 2302of the handle 2301. The cylindrical device 2406 shown in FIG. 24 is thetransducer assembly, such as the transducer assembly 316 of FIG. 3.Located above the transducer assembly 2406 is the generator 2404. Thetwo ultrasonic-movement-generation assembly components 2404, 2406, whenplaced inside the covering shell 2304, advantageously can be easilydetached from the handle 2301 and sterilized or replaced as a completeunit. In one embodiment, the ultrasonic-movement-generation assemblycomponents 2404, 2406 are hermetically sealed inside the cover 2304,rendering the ultrasonic-movement-generation assembly 2303 autoclavableso that it can be attached to and used with several different devices.The ultrasonic-movement-generation assembly 2303 is coupled to thesecond portion 2310 of the handle 2302 through a port 2408. The port2408, when the ultrasonic-movement-generation assembly 2303 is removed,is visible and accessible from an exterior of the handle 2301. However,once the ultrasonic-movement-generation assembly 2303 is snapped ontothe handle 2301, the handle 2301 and ultrasonic-movement-generationassembly 2303 could be shaped to create a water-tight seal with oneanother and prevent moisture on the exterior of either one of the handle2302 and ultrasonic-movement-generation assembly 2303 from entering thejunction between the handle 2301 and ultrasonic-movement-generationassembly 2303.

FIG. 24 also shows a battery door 2412 that, when opened, allows abattery 304 to be inserted into the battery-holding compartment 2410and, when closed, as shown in FIG. 24, creates a water-tight seal (e.g.,aseptic seal) between the interior of the handle 2302, shown in thecutaway view of FIG. 24, and the exterior of the handle 2302, shown inthe elevational view of FIG. 23.

Once the ultrasonic-movement-generation assembly 2303 is coupled to thehandle 2301, the driving-wave generation circuit, or “generator” 2404,is placed in electrical contact with the battery-holding compartment2410 so that a battery 304, when inserted, can supply power to theultrasonic-movement-generation assembly 2303. Additionally, referringnow to FIG. 25, when an ultrasonic-movement-generation assembly 2502 iscoupled to a handle 2514, the transducer 2516 is caused to berealeasably physically coupled to a waveguide 2504, 2508 through thetransducer attachment port 2518 and waveguide attachment port 2520. Itis envisioned that the transducer assembly 2516 can be temporarilylocked into a fixed rotational position so that the waveguide 2504 canbe attached to the threads 1610 (see, e.g., FIG. 16) with sufficientforce. This physical coupling between the waveguide 2504 and thetransducer assembly 2516 allows the transducer assembly 2516 to impartmovement to the waveguide 2504 when power is applied to the transducerassembly 2516.

The gun 2500 has a spindle 2506 that attaches to the waveguide 2508. Thespindle 2506 has indentions that allow a surgeon to easily rotate thespindle 2506 and, therefore, the attached waveguide 2508 and transducerassembly 2516 that is attached to the waveguide 2508. Such aconfiguration is useful for obtaining the proper cutting-blade angleduring surgery. To provide for this rotation, in one exemplaryembodiment, the transducer assembly 2516 is able to rotate freely withinthe transducer housing 2510.

During initial coupling of the transducer assembly 2516 and waveguide2504, all that is needed is that one of the transducer assembly 2516 andthe waveguide 2504 remains relatively stationary with respect to theother. According to one exemplary embodiment of the present invention,when the transducer assembly 2516 is located inside the housing2510—where it cannot be readily secured by the operator, for example, byholding it steady by hand when the waveguide 2508 is being secured—theultrasonic-movement-generation assembly 2502 is provided with a button(not shown) that slides into a recess in the housing 2510 or,alternatively, by fixing the rotation of the transducer assembly 2516 ata maximum rotational angle so that, once the maximum rotation isreached, for example, 360 degrees of rotation, no additional rotation ispossible and the waveguide 2504 can be screwed thereon. Of course, amaximum rotation in the opposite direction will allow the waveguide 2504to be removed as well.

FIG. 26 shows one example of how the generator assembly 2512 andtransducer assembly 2516 are electrically coupled so that a physicalrotation of the transducer assembly 2516 with respect to the generatorassembly 2512 is possible. In this example, the generator assembly 2512has a pair of contacts 2602 protruding from its underside, adjacent thetransducer assembly 2516. Proximity of the transducer assembly 2516 tothe generator assembly 2512 places one of the pair of contacts 2602(circled) in physical communication with a pair of contact rings 2604 atthe transducer body 2610 so that a driving signal can be steadilyapplied to the transducer assembly 2516 when needed. Advantageously, thepair of contacts 2602 maintains electrical contact regardless of anangle of rotation of the transducer assembly 2516. Therefore, thetransducer assembly 2516 can rotate without any limitations as to themaximum angle or number of rotations. In one embodiment of the presentinvention, the waveguide-movement-generation assembly 2303 can include abattery 304. This embodiment is advantageous, as it allows the handleportion 2302 to be made smaller or cheaper, as battery contacts are notnecessary in the handle portion 2302.

Transducer

In another non-illustrated embodiment, the cover 2304 is not present andthe transducer assembly 2516 and generator assembly 2512 assemblies areindividually covered, i.e., sealed and autoclavable, with each coverbeing exposed and accessible to a user's fingers. With the main cover2304 not present, an operator attaching the transducer assembly 2516 tothe waveguide 2508 has direct access to the transducer assembly 2516 andis able to hold both the transducer assembly 2516 and the waveguide 2508and turn either one relative to the other during coupling.

FIGS. 27-30 show more detailed views of exemplary embodiments of thedevice and the trigger mechanisms. It is noted that there is adifference between the activation trigger of the device shown in FIGS.19-22 and the trigger shown in FIGS. 23-30. Specifically, in the device1800 of FIGS. 19-22, and shown more particularly in FIG. 21, the upperhandle portion 1802 is hollow. Because it is hollow, the trigger 2102can be a thick object that, when squeezed, is able to retract at leastpartially into the interior of the handle 2101. The thick trigger 2102has the advantage of preventing a user's fingers from getting pinchedwhen the trigger 2102 is squeezed. In contrast to this embodiment, theembodiment of FIG. 24 includes a battery 304 within the interior of thehand grip 2302. Because the interior of the hand grip 2302 is filledwith the battery 304, the trigger 2308 cannot retreat inside the handgrip 2302 when actuated, as does the trigger 2102 of FIG. 21. For thisreason, the trigger 2308 is thinner than the trigger 2102 of FIG. 21 inthe trigger actuation direction and simply moves toward the hand grip2302 during actuation (it does not enter the interior of the hand grip2302, or enters it only minimally).

Advantageously, to prevent a user's finger from getting caught betweenthe trigger 1318, 1418, 2308 and the hand grip 1308, 1408, 2302, thetrigger includes a protrusion 1306, 2306 extending from the hand grip1308, 2302 and preventing the user's finger from moving up and under thetrigger 1318, 2308. Not only does the protrusion 1306, 2306 prevent theuser's finger from getting pinched and causing possible discomfort, theprotrusion 1306, 2306 also prevents the user's finger from interferingwith functioning of the trigger 1318, 2308.

In an alternative exemplary embodiment to the gun device, FIGS. 31 to 34illustrate an entirely hand-held and fully self-contained cautery andcutting device 3300. This cutting device 3300 reduces the size of thepower supply 3302 considerably. Here, in comparison to the previousembodiments, the waveguide 3304 is reduced in length. All of the powermodification components (the control, drive, and matching circuits 304,306, 308) and the power supply 3302 reside at the handpiece 3310. As inthe other embodiments described above, the pen shaped device shown inFIGS. 31 to 34 could have, in accordance with one embodiment, a sealedbody 3302, where the body 3302 housing the power modification components(the control, drive, and matching circuits 304, 306, 308) and the powersupply 3302 is autoclavable and the waveguide 3304 is simply replacedfor each procedure. Alternatively, the body 3102 could open up andreceive the power modification components (the control, drive, andmatching circuits 304, 306, 308) and the power supply 3302 in an aseptictransfer, similar to the device shown in FIG. 21 and described above.

In further exemplary embodiments of the present invention, the powersupply can be separated from the handpiece and can, for example, be wornon a physician's belt. An example of such embodiments can be seen inFIGS. 34 to 38. In these embodiments, the base 3700, shown in FIG. 37,has a body 3706 that houses a self-contained power source (i.e., abattery) and a generator circuit operable to generate an output waveformand is sized to be handheld. The base 3700 is connected through acommunications and power tether cord 3702, illustrated diagrammaticallyin the figures with a dashed line, to the pen-shaped ultrasonicwaveguide handle 3600, shown in FIGS. 34-36. When in operation, thetransducer 3602 within the handle 3600 is driven by a plurality ofdriving waves output from the waveform generator within the body 3706.

The base 3700 has a user interface 3704 that can be used to communicatedata and carry out functions of the device, such as testing andoperation. Through the user interface 3704, the device can be tested inthe sealed package without even opening the package. For instance, inone embodiment, a user can press one or more non-illustrated buttons(physical or electronic) in a given sequence (e.g., 5 times in a row)and, thereby, cause the user interface 3704 to display a status of thebattery and/or a status of the logic circuitry, all without having toremove it from the sealed package. This is helpful in case of a defect,such as a bad battery, as the purchaser would be able to return thedevice to the manufacturer before use and, thereby, prove non-use of thedevice to receive credit. In this embodiment, all of the powermodification components (the power supply 304, the processor 302, thedrive circuit 308, and the matching circuit 312) reside in the base3700.

The base 3700 is also provided with a non-illustrated clothingattachment mechanism that can be a simple belt clip, or any other way ofattaching a device to a wearer. The clothing attachment mechanism allowsa surgeon or nurse to wear the base 3700 during a surgery so that thecord 3702 will always be of sufficient length, i.e., as long as his armcan reach, no matter where the surgeon is standing.

For ease of use, the cautery/cutting device 3400 is shaped to fit into asurgeon's hand. The shape illustrated in FIG. 34 is, therefore, onlyexemplary. Another exemplary shape for the pen device 3600 is shown inFIGS. 35 and 36 and is similar to a writing pen so that the surgery canbe carried out with the device 3600 to approximate writing—a processthat is comfortable to most physicians. The pen 3400, 3600 includes allof the transducer components—the transducer 3402, 3602, the protectivecannula 3404, 3604, and the waveguide 3406, 3606.

In various other embodiments of the present invention, one or more ofthe components, together or separate, can be removed from or exchangedbetween the handpiece 2300, 3300, 3400, 3600 and the base 3700 forservice, replacement, storage, inspection, or other purposes as desired.

The component(s) of the devices described herein (whether separately, asa unit, or a frame to which they are connected to one another) canimplement a confirmation process for ensuring that the variouscomponent(s) can or should be used in or with the device. For instance,the components can perform a check (possibly with encryption) to seewhether they match the particular handpiece 2300, 3300, 3400, 3600 orbase 3700, i.e., to see if they have the correct manufacturer/modelnumber to work with the part in which or to which it is connected.

In an exemplary safety embodiment for any of the configurations of theinvention, the system can have a safety mechanism where the surgeonusing the device is grounded to the circuit 300. In the event thewaveguide 318, 3306, 3406, 3606 accidentally makes contact with thesurgeon, the device senses this grounding and immediately ceasesmovement of the waveguide 318, 3306, 3406, 3606, thereby instantlypreventing the surgeon from cutting him/herself. Because the hand-heldinstrument 2300, 3300, 3400, 3600, 3700 is not connected to earthground, it will be possible to provide a safety circuit that can sensecontact with the surgeon and interrupt ultrasonic power delivery. Forexample, a capacitive contact patch located on the hand grip 2302, 3310,3400, 3600, 3700 is connected to a capacitive-touch sensing circuit(such as is used for capacitive switching and known to those in the art)and disposed to detect contact of the working tip with the surgeon. Whensuch contact is detected, the drive circuit of the instrument will beshut down to avoid applying cutting energy to the surgeon. Such asensing circuit would be impractical in systems of the prior art, wherethe handpiece is connected to a large piece of earth-grounded electricalequipment.

FIG. 39 shows another exemplary embodiment of the present invention,which includes a “smart” or “intelligent” battery 3902. The smartbattery 3902 is used to power a surgical or other device, such as thegun 3900. However, the smart battery 3902 is not limited to the gun 3900and, as will be explained, can be used in a variety of devices, whichmay or may not have power (i.e., current and voltage) requirements thatvary from each other. The smart battery 3902 is advantageously able toidentify the particular device to which it is electrically coupled. Itdoes this through encrypted or unencrypted identification methods. Forinstance, the battery 3902 can have a connection portion, such asportion 3904 shown in FIG. 39. The gun's handle 3901 can also beprovided with a device identifier 3906 communicatively coupled to thebattery-holding compartment 3908 and operable to communicate at leastone piece of information about the handle 3901. This information canpertain to the number of times the handle 3901 has been used, the numberof times a TAG unit 3910 has been used, the number of times a waveguide(not shown) has been used, the type of waveguide connected to the handle3901, the type or identity of TAG 3910 connected to the handle 3901, ormany other characteristics. When the battery 3902 is inserted in thehandle 3901, the connection portion 3904 makes communicating contactwith the device identifier 3906. The handle 3910, through hardware,software, or a combination thereof, is able to transmit information tothe smart battery assembly 3902. This communicated identifier isreceived by the connection portion 3904 of the smart battery assembly3902.

In one embodiment, once the smart battery assembly 3902 receives theinformation, the communication portion 3904 is operable to control theoutput of the battery assembly 3902 to comply with the device's specificpower requirements. By integrating a microcontroller 3916 in thecommunication portion 3904 of the battery assembly 3902, it is no longerrequired that a programmable device be placed in the disposable handleportion 3901. As a result, the handle may be sterilized by gammaradiation, which is more economical than other sterilization measures.

In accordance with another embodiment, the battery-holding compartment3908 has a battery ejector device 3912 that extends at least partiallywithin the battery-holding compartment 3908 and is able to cause atleast a portion of the battery 3902 to be ejected from thebattery-holding compartment 3908. This prevents an operator from havingto reach his or her potentially soiled or otherwise non-sterile fingersinside the device in order to remove the battery assembly 3902. In oneembodiment, the battery-holding compartment 3908 is activated by amovement of the door from the closed position to the open position. Inother words, once the door is opened, the batter 3902 partially ejectsout of the compartment 3908.

In some exemplary embodiments of the present invention, the transducerassembly 1302, shown in FIG. 15, contains additional circuit components,such as the tank circuit 312 shown in FIG. 3. In practice, the tankcircuit 312 is tuned to match the transducer to which it feeds.Therefore, transducers and tank circuits are best matched if they remainas a pair and are not placed in combination with other device. Inaddition, if each transducer assembly 1302 had its own tank circuit, thesmart battery 3902 could feed different frequencies to the differenttransducer assemblies 1302, the frequencies being respectively matchedto a particular blade and waveguide assembly. Two popular frequenciesfor ultrasonic surgery devices are 55 kHz and 40 kHz.

In one exemplary embodiment, the communication portion 3904 includes aprocessor, such as processor 302, and a memory, such as memory 326,which may be separate or a single component. The processor 302, incombination with the memory 326, is able to provide intelligent powermanagement for the gun device 3900. This embodiment is particularlyadvantageous because an ultrasonic device, such as device 300, has apower requirement (frequency, current, and voltage) that may be uniqueto the device 300. In fact, device 300 may have a particular powerrequirement or limitation for one dimension or type of waveguide 318 anda second different power requirement for a second type of waveguidehaving a different dimension, shape, and/or configuration.

If a set of different devices having different waveguides exists, theneach of the waveguides would have a respective maximum allowable powerlimit. Exceeding the power limit overstresses the waveguide andeventually causes it to fracture. One waveguide from the set ofwaveguides will naturally have the smallest maximum power tolerance.Because the prior-art batteries lack intelligent battery powermanagement, the output of prior-art batteries must be limited by a valueof the smallest maximum allowable power input for thesmallest/thinnest/most frail waveguide in the set that is envisioned tobe used with the device/battery. This would be true even though larger,thicker waveguides could later be attached to that handle and, bydefinition, allow a greater force to be applied.

This limitation is also true for maximum battery power. If one batteryis designed to be used in multiple devices, its maximum output powerwill be limited to the lowest maximum power rating of any of the devicesin which it is to be used. With such a configuration, one or moredevices or device configurations would not be able to maximize use ofthe battery because the battery does not know the device's limits.

In contrast thereto, exemplary embodiments of the present inventionutilizing the smart battery 3902 are able to intelligently circumventany previous limitation of ultrasonic devices. The smart battery 3902can produce one output for one device or a particular deviceconfiguration and the same battery 3902 can later produce a differentoutput for a second device or device configuration. This universal smartbattery surgical system lends itself well to the modern operating roomwhere space and time are at a premium. By having a single battery packthat operates many different devices, the nurses can easily manage thestorage and retrieval of the packs. Advantageously, the smart batterysystem requires only one type of charging station, thus increasing easeand efficiency of use and decreasing cost.

In addition, other devices, such as an electric stapler, may have acompletely different power requirement than that of the ultrasonicdevice 300. With the present invention, a single smart battery 3902 canbe used with any one of an entire series of devices and is able totailor its own power output to the particular device in which it isinstalled. In one embodiment, this power tailoring is performed bycontrolling the duty cycle of a switched mode power supply, such asbuck, buck-boost, boost, or other configuration, integral with orotherwise coupled to and controlled by the smart battery 3902.

In other exemplary embodiments, the smart battery 3902 can dynamicallychange its power output during device operation. For instance, in vesselsealing devices, power management is very important. In these devices,large constant current values are needed. The total power output needsto be adjusted dynamically because, as the tissue is sealed, itsimpedance changes. Embodiments of the present invention provide thesmart battery 3902 with a variable maximum current limit. The currentlimit can vary from one application (or device) to another, based on therequirements of the application or device.

More specifically, referring to FIG. 44, an ultrasonic surgical device4400 has an ultrasonic waveguide 4402 with one of a set of differentwaveguide types. An ultrasonic transducer 4404 is physically coupled tothe waveguide 4402 and is operable to impart ultrasonic movement to theultrasonic waveguide 4402. A cordless ultrasonic-movement-generationassembly 4406 is connected to either the waveguide or the transducer andis operable to generate and deliver a driving-wave frequency and adriving-wave power to the transducer 4404. Because the device 4400 isable to accept and drive waveguides 4402 of varying dimensions, thedevice 4400 is provided with a waveguide detector 4408 coupled to theultrasonic-movement-generation assembly 4406 and operable to detect thetype (e.g., the dimensions) of the waveguide 4402 attached to thetransducer 4404 and to cause the ultrasonic-movement-generation 4406assembly to vary the driving-wave frequency and/or the driving-wavepower based upon the detected waveguide type. The waveguide detector4408 can be any device, set of components, software, electricalconnections, or other that is/are able to identify at least one propertyof a waveguide 4402 connected to the device 4400.

In a further exemplary embodiment, the smart battery 3902 stores in itsmemory 326 a record of each time a particular device is used. Thisrecord can be useful for assessing the end of a device's useful orpermitted life. For instance, once a device is used 20 times, all suchbatteries 3902 connected to the device will refuse to supply powerthereto—because the device is defined as a “no longer reliable” surgicalinstrument. Reliability is determined based on a number of factors. Onefactor can be wear; after a certain number of uses, the parts of thedevice can become worn and tolerances between parts exceeded. This wearcan lead to an unacceptable failure during a procedure. In someexemplary embodiments, the smart battery 3902 can recognize which partsare combined and even how many uses each part has experienced. Forinstance, looking at FIG. 14, if the battery 1700 is a smart battery, itcan identify both the gun 1300, as well as the particular transducerassembly 1302. A memory within the smart battery 3902 can record eachtime the transducer assembly 1302 is operated. If each transducerassembly 1302 has an individual identifier, the smart battery 3902 cankeep track of each transducer assembly's use and refuse to supply powerto that transducer assembly 1302 once the gun 1300 or the transducerassembly 1302 exceeds its maximum number of uses. The TAG, stapler,vessel sealer, etc. circuitry can include a memory chip which recordsthis information also. This way, any number of smart batteries can beused with any number of TAGs, staplers, vessel sealers, etc. and stillbe able to determine the total number of uses, or the total time of use(through use of clock 330), or the total number of actuations etc. ofeach TAG, stapler, vessel sealer etc.

Referring now to FIG. 40, another embodiment of the present invention isshown. In the embodiment of FIG. 40, the device 4000 is provided with aplurality of buttons 4002 a-n, although not all can be seen in theleft-side view of FIG. 40. These buttons can have various functions thatpertain to operation of the device 4000. As explained above, previousdevices were tethered by a cord 208 to a desktop box 202. If a prior-artdevice wished to add an additional function, associated with a button,then an additional communication wire would need to be added to thenon-changeable strand of wires in the tether 208. The addition of wiresrenders the tether even less desirous, as the surgeon must work with andsupport the ever-increasing bundle of wires. The present invention isimpervious to this disadvantage because all communication is containedwithin the handle itself and no external wires are needed. The device4000 will generally operate the same and weigh the same, no matter howmany buttons are added.

In accordance with yet another embodiment, the present invention isprovided with a display screen 4004 that conveys visual information toan operator. The visual information can be, for instance, the number ofuses a particular waveguide has been subjected to, the battery voltage,the status of the device, such as indicating a non-engaged condition ofthe device components, button states, warnings, and many others.

The present invention, according to an embodiment, as shown in FIG. 45,has a window 4502 on the compartment door 4504 that allows a user toview a display screen 4506 on a movement-generation assembly within thecompartment. 4508.

In one embodiment of the present invention, as shown in FIG. 46, theultrasonic surgical device 4600 includes a cordless unitary housing 4602sized to fit within a surgical instrument handle 4604. The housing 4602houses a self-contained power source 4606 and a power source controlcircuit 4608 that is electrically coupled to the power source 4606 andis operable to control distribution of power from the power source 4606.The housing 4602 also holds an ultrasonic waveform-generating circuit4610 electrically coupled to the control circuit 4608 and operable tooutput a waveform sufficient to drive an ultrasonic transducer of theultrasonic surgical instrument 4600. In this embodiment, the ultrasonicwaveguide driving assembly 4601 can be inserted into the inexpensivehandle 4604, used for a single surgery, the handle 4604 disposed of, andthe assembly can then be inserted and used in multiple other handles toperform additional surgeries. In this embodiment, all of the expensivecomponents are reused and do not need to be aseptically sealed sincethey are contained within a battery-holding compartment 4612 of thehandle 4604 and are never exposed to the operating environment.

FIG. 47 shows yet another embodiment of the present invention where, inthis case, the transducer remains separate from theultrasonic-signal-generator assembly, which allows it to be grasped whenthe waveguide is being attached to the transducer. The inventiveultrasonic surgical assembly 4700 includes an ultrasonic waveguide 4702,an ultrasonic-signal-generator assembly 4704, an ultrasonic transducer4706, a removable battery 4708, and a surgical handle 4710.

The ultrasonic-signal-generator assembly 4704 includes a shell 4712, aselectively removable securing connector 4714 on the shell 4712, anultrasonic-driving-wave-signal generating circuit 4716 housed within theshell 4712, power contacts 4711 electrically coupling theultrasonic-driving-wave-signal generating circuit 4716 to the battery4708, and output contacts 4713 supplying an ultrasonic driving waveproduced by the ultrasonic-driving-wave-signal generating circuit 4716when in operation.

The surgical handle 4710 includes a first handle body portion 4718 andan attached second hand body portion 4719. The first handle body portion4718 defines therein an aseptically sealable battery-holding compartment4720 that is selectively exposed to the environment and is able toaseptically removably hold therein the removable battery 4708. Contacts4721 within the compartment 4720 electrically connect the battery 4708therein to the ultrasonic-signal-generator assembly 4704.

The second handle body portion 4719 has a waveguide attachment dock4724, which is exposed to the environment and has a first couple 4726operable to selectively removably rotatably secure the ultrasonicwaveguide 4702 to the second handle body portion 4719. The second handlebody portion 4719 also has a transducer attachment dock 4728 whichopposes the waveguide attachment dock 4724. The transducer attachmentdock 4728 is exposed to the environment and has a second couple 4730operable to selectively removably rotatably secure the ultrasonictransducer 4706 to the second handle body portion 4719 and to theultrasonic waveguide 4702 when the ultrasonic waveguide 4702 is coupledto the waveguide attachment dock 4724. The couples 4726 and 4730 cansimply be aligned passageways that place the waveguide 4702 into axialalignment with the transducer 4706. Of course, the couples 4706 and 4730can provide more structure, such as threads, that actually hold thewaveguide 4702 and/or transducer 4706 to the handle or to each other.

Additionally, the second handle body portion 4719 has anultrasonic-signal-generator assembly dock 4727 that is exposed to theenvironment and shaped to removably secure the securing connector 4714of the ultrasonic-driving-wave-signal generating circuit 4716 to thesecond handle body portion 4719. The assembly dock 4727 also aligns theultrasonic-driving-wave-signal generating circuit 4716 so that, when thecircuit 4716 and the transducer 4706 are connected to the second handlebody portion 4719, the ultrasonic-driving-wave-signal generating circuit4716 and the transducer 4706 are electrically connected.

Advantageously, the ultrasonic transducer 4706 is rotatable with respectto the second handle body portion 4719 and the waveguide attachment dock4724 is shaped to rotatably connect the ultrasonic waveguide 4702 in thewaveguide attachment dock 4724 to the ultrasonic transducer 4706 in thetransducer attachment dock 4728 through the second handle body portion4719. In this way, the waveguide attachment dock 4724 and the transducerattachment dock 4728 directly physically couple the ultrasonic waveguide4702 and the ultrasonic transducer 4706 and permit a correspondingrotation of the ultrasonic transducer 4706 with respect to the secondhandle body portion 4719 when at least one of the ultrasonic waveguide4702 and the ultrasonic transducer 4706 rotates.

Although not shown in the view of FIG. 47 (but see FIGS. 39 and 46), thebattery compartment 4720 has a compartment door 3914 that is connectedmovably to the second handle body portion 4719 and has an open positionpermitting entry and removal of the removable battery 4708 respectivelyinto and from the compartment 4720 and a closed position asepticallysealing the compartment 4720 from the environment. A set of conductivepower leads 4721 in the battery-holding compartment 4720 are shaped toelectrically connect the battery 4708 to the ultrasonic-signal-generatorassembly 4704 at least when the battery 4708 is sealed in thebattery-holding compartment 4720.

In a further exemplary embodiment, the assembly 4700 includes a memory4732 electrically connected at least to the ultrasonic-signal-generatorassembly dock 4727. The memory 4732 stores a record of each time thedevice is used. This record can be useful for assessing the end of thedevice's useful or permitted life. For instance, once the device is usedtwenty (20) times, the device can be programmed to no longer function(e.g., because the device is, then, a “no longer reliable” surgicalinstrument). The memory 4732 can also store a number of uses of thedevice's peripherals. For example, after a certain number of uses, theparts of the device can become worn and tolerances between partsexceeded. This wear can lead to an unacceptable failure during aprocedure. In some exemplary embodiments, the memory 4732 stores arecord of the parts that have been combined with the device and how manyuses each part has experienced.

In some embodiments, as explained above, the memory 4732 is on thebattery and the handle body is provided with a device identifier that iscommunicatively coupled to the battery-holding compartment and isoperable to communicate to the smart battery at least one piece ofinformation about the ultrasonic surgical assembly 4700, such as the usehistory discussed in the preceding paragraph, a surgical handleidentifier, a history of previous use, and/or a waveguide identifier.

The perspective view of the assembly 4700 in FIG. 48 shows an O-ring4802 around the transducer 4706. The O-ring 4802 helps protect and sealthe interior of the device 4700 from liquids that enter around the shell4712. Once the transducer 4706 is inserted into the transducerattachment dock 4728, the O-ring 4802 also holds the transducer 4706 inplace. FIG. 48 further shows a view of a pair of transducer inputcontacts 4804, 4806 that electrically couple to the connectors 4713 toprovide the driving signal to the transducer 4706.

FIG. 49 is a perspective view of the inventive ultrasonic surgicalassembly 4700 fully assembled. The ultrasonic-signal-generator shell4712 covers and obscures the details of the ultrasonic-signal-generatorassembly 4704, the transducer housing 1506 obscures the details of thetransducer 1606, and the handle body 4710 obscures the interior elementsof the handle portions 4718, 4719.

FIG. 50 shows an elevational view of a variation of the ultrasonicsurgical assembly shown in FIGS. 47 and 48. Theultrasonic-signal-generator assembly 5001 includes a shell 5012, anultrasonic-driving-wave-signal generating circuit 5005 housed within theshell 5012, power contacts 5011 electrically coupling theultrasonic-driving-wave-signal generating circuit 5005 to the battery5008, and output contacts 5013 supplying an ultrasonic driving waveproduced by the ultrasonic-driving-wave-signal generating circuit 5005when in operation.

In the embodiment of FIG. 50, the transducer 5006 is provided with anannular channel 5004 that aligns with a wall 5002 on the interior of theultrasonic-signal-generator shell 5012. The transducer channel 5004 andthe wall 5002 prevent the transducer 5006 from moving laterally withrespect to the ultrasonic-driving-wave-signal generating circuit 5005(and longitudinally with respect to the waveguide 4702), whilecontinuing to allow the transducer 5006 to rotate within theultrasonic-signal-generator assembly 5001. In this embodiment, thetransducer 5006 and the ultrasonic-signal-generator assembly 5001,similar to the embodiments of FIGS. 23 to 30, 39, 40, and 42 to 44,create a single, removable ultrasonic-movement generation assembly 5003,except that, in this embodiment, the transducer 5006 can be grasped, atan exposed proximal end 4810, by the user's hands during attachment anddetachment to the waveguide 4702 and during use of the device toposition the end effector 2504 (not shown in this view) of the waveguide4702.

FIG. 51 is a process flow diagram illustrating exemplary steps for useof the present invention. The process begins at step 5100 and movesdirectly to step 5102 where an ultrasonic surgical assembly 4700 isassembled by first coupling an ultrasonic-signal-generator assembly 4704to a handle body 4710. In step 5104, an ultrasonic transducer 4706 iscoupled to the handle body 4710 by inserting it below or through theultrasonic-signal-generator assembly 4704 so that itsultrasonic-movement-producing distal end 4808 (shown in FIG. 48) isinserted into the transducer attachment dock 4728. In step 5106, awaveguide 4702 is coupled to the handle body 4710 by inserting thewaveguide 4702 into the waveguide attachment dock 4724. It should benoted that the steps 5102-5106 do not have to be in the sequence justpresented and can be in any order without affecting the presentinvention.

In step 5108, a user grasps the proximal end 4810 of the ultrasonictransducer 4706. As shown in FIG. 49, grasping the proximal end 4810 ofthe ultrasonic transducer 4706 is simple, because the proximal end 4810extends beyond the ultrasonic-signal-generator shell 4712 that shieldsthe ultrasonic-signal-generator assembly 4704. Next, in step 5110,either the waveguide 4702 or the ultrasonic transducer 4706 is rotatedwith respect to the other to fixedly couple the waveguide 4702 to theultrasonic-movement-producing distal end of the transducer 4706. Thecoupling is accomplished, for example, through the distal threaded end1610 of the transducer, as shown in FIG. 16, and a non-illustratedopposing set of threads in the proximal end of the waveguide 4702. Oncecoupled, both the ultrasonic transducer 4706 and the waveguide 4702rotate in relation to the handle body 4710 and theultrasonic-signal-generator assembly 4704.

Because the ultrasonic transducer 4706 is completely separable from theultrasonic-signal-generator assembly 4704, in an additional optionalstep, any of the components can be individually removed and replaced.For instance, the ultrasonic transducer 4706 can be removed from thewaveguide 4702 and the handle body 4710 and a replacement ultrasonictransducer 4706 can be attached to the waveguide 4702 and handle body4710. The process ends at step 5112.

FIG. 52 shows a process flow diagram that pertains to the embodiment ofthe ultrasonic surgical assembly 5000 shown in FIG. 50. As explainedabove, the difference between the ultrasonic surgical assembly 4700 ofFIGS. 47 to 49 and the ultrasonic surgical assembly 5001 of FIG. 50 isthat, in the embodiment of FIG. 50, the ultrasonic transducer 5006 ispart of the ultrasonic-movement-generation assembly 5001. Therefore, theprocess flow diagram of FIG. 52 shares several steps with the processflow diagram of FIG. 51. The process begins at step 5200 and movesdirectly to step 5202 where the ultrasonic-movement-generator assembly5001, which includes both the ultrasonic-signal-generation assembly 5001and the ultrasonic transducer 5006, is coupled to the handle body 4710.In step 5204, the waveguide 4702 is coupled to the handle body 4710 byinserting the waveguide 4702 into the waveguide attachment dock 4724. Itshould be noted that the steps 5202 and 5204 do not have to be in thesequence just presented and can be in any order without affecting thepresent invention.

In step 5206, a user grasps the proximal end 4810 of the ultrasonictransducer 5006. Once assembled, the embodiment of FIG. 50 is similar tothe embodiment shown in FIG. 49. Grasping the proximal end 4810 of theultrasonic transducer 5006 is simple, because the proximal end 4810extends beyond the ultrasonic-signal-generator shell 5012 that shieldsthe ultrasonic-signal-generator assembly 5001. Next, in step 5208,either the waveguide 4702 or the ultrasonic transducer 5006 is rotatedwith respect to the other to fixedly couple the waveguide 4702 to theultrasonic-movement-producing distal end of the transducer 5006. Oncecoupled, both the ultrasonic transducer 5006 and the waveguide 4702rotate in relation to the handle body 4710 and theultrasonic-signal-generator assembly 5001. The process ends at step5210.

As has been described, the present invention provides a small andefficient hand-held ultrasonic cutting device that is self-powered and,therefore, cordless. Alternatively, and/or additionally, the inventionhas a separate body-worn pack that houses any combination of the controlelectronics and the self-contained power supply. In either embodiment,the expensive set-top box is eliminated entirely. The invention provideslow-voltage or battery-voltage switching or wave-forming stages prior tothe transducer. Advantageously, the device allows a user to operatecompletely free of cords or other tethering devices. The presentinvention, by “marrying” all of the frequency sensitive componentswithin one place (e.g., the handle), also eliminates any inductivelosses that occur between prior art set-top boxes and handpieces—adisadvantage suffered by all prior-art ultrasonic cautery/cuttingdevices. Because of the close coupling between the drive circuit 308 andthe matching network 312, the overall power modification circuit istolerant of higher Q factors and larger frequency ranges.

The present invention provides additional advantages in the way thedevice is kept sterile. Because the inventive device is a fraction of asize of the prior art devices, the driving circuit can be placed withinthe handle. The handle, transducer, waveguide, and blade are sterilizedand the handle has a door that opens, allowing the battery and drivingcircuits, which are outside the sterile field, to be dropped inside thehandle. When the door is closed, the non-sterile portions are sealedwithin the handle.

Although specific embodiments of the invention have been disclosed,those having ordinary skill in the art will understand that changes canbe made to the specific embodiments without departing from the spiritand scope of the invention. The scope of the invention is not to berestricted, therefore, to the specific embodiments, and it is intendedthat the appended claims cover any and all such applications,modifications, and embodiments within the scope of the presentinvention.

1. A method of maintaining a constant movement of a cutting blade of anultrasonic waveguide, which comprises: providing: an ultrasonictransducer operable to convert a received motional current into amovement of a cutting blade of an ultrasonic waveguide; a measurementcircuit connected in a parallel configuration with the ultrasonictransducer; supplying current through a set of connection points of theparallel configuration with a variable power source to, thereby, createthe motional current in the ultrasonic transducer; and regulating themotional current with a current controller by varying an output of thepower source, thereby maintaining a substantially constant rate ofmovement of the cutting blade across a variety of cutting loads.
 2. Themethod according to claim 1, wherein: the ultrasonic transducer has afirst capacitance in a parallel configuration with a seriesconfiguration of a resistance, an inductance, and a second capacitance;and the motional current flows through the series configuration.
 3. Themethod according to claim 2, wherein the measurement circuit iscomprised of a third capacitance in a parallel configuration with thefirst capacitance.
 4. The method according to claim 3, wherein thevariable power source is coupled to the third capacitance and theultrasonic transducer.
 5. The method according to claim 4, which furthercomprises carrying out the motional current regulating step by varyingan output of the power source based upon a product of the currentflowing through the third capacitance multiplied by a ratio between avalue of the first capacitance and a value of the third capacitancesubtracted from a total current flowing into the ultrasonic transducer.6. The method according to claim 1, wherein: the current controllercomprises a processor; and the variable power source comprises a phaselocked loop communicatively coupled to the processor, and which furthercomprises: determining a frequency of movement of the cutting blade withthe phase locked loop; and storing a last frequency of blade movement ina memory communicatively coupled to the processor.
 7. The methodaccording to claim 1, which further comprises: providing a clampingmechanism having a range of clamping force values and being operable toplace material in physical contact with the cutting blade;communicatively coupling the current controller to the clampingmechanism; and varying the motional current with the current controllerbased upon a given clamping value within the range of clamping values.8. The method according to claim 1, wherein the variable power sourcecomprises a removable battery.
 9. The method according to claim 1, whichfurther comprises providing a disposable handle body with: a portiondefining a battery-holding compartment having at least two batterycontacts; a waveguide attachment dock exposed to the environment andshaped to accept the ultrasonic waveguide therein; a transducerattachment dock exposed to the environment and shaped to place theultrasonic transducer in coaxial alignment with the ultrasonic waveguidewhen the ultrasonic waveguide is disposed within the waveguideattachment dock; and an ultrasonic-signal-generator assembly dockexposed to the environment and shaped to substantially simultaneously:selectively removably secure at least the ultrasonic transducer to thehandle body; place an end of the ultrasonic transducer within thetransducer attachment dock; and electrically couple at least theultrasonic transducer to the at least two battery contacts.
 10. A methodof maintaining a constant movement of a cutting blade of an ultrasonicwaveguide, which comprises: providing: an ultrasonic transducer operableto convert a received motional current into a movement of a cuttingblade of an ultrasonic waveguide, the ultrasonic transducer having afirst capacitance in a parallel configuration with a seriesconfiguration of a resistance, an inductance and a second capacitance,whereby the motional current flows through the series configuration; anda third capacitance in a parallel configuration with the firstcapacitance; supplying current through a set of connection points of theparallel configuration with a variable power source coupled to the thirdcapacitance and the ultrasonic transducer to, thereby, create themotional current in the ultrasonic transducer; and regulating themotional current with a current controller by varying an output of thepower source based upon a product of the current flowing through thethird capacitance multiplied by a ratio between a value of the firstcapacitance and a value of the third capacitance subtracted from a totalcurrent flowing into the ultrasonic transducer, thereby maintaining asubstantially constant rate of movement of the cutting blade across avariety of cutting loads.
 11. The method according to claim 10, wherein:the current controller comprises a processor; and the variable powersource comprises a phase locked loop communicatively coupled to theprocessor, and which further comprises: determining a frequency ofmovement of the cutting blade with the phase locked loop; and storing alast frequency of blade movement in a memory communicatively coupled tothe processor.
 12. The method according to claim 10, which furthercomprises: providing a clamping mechanism having a range of clampingforce values and being operable to place material in physical contactwith the cutting blade; communicatively coupling the current controllerto the clamping mechanism; and varying the motional current with thecurrent controller based upon a given clamping value within the range ofclamping values.
 13. The method according to claim 10, wherein thevariable power source comprises a removable battery.
 14. The methodaccording to claim 10, which further comprises providing a disposablehandle body with: a portion defining a battery-holding compartmenthaving at least two battery contacts; a waveguide attachment dockexposed to the environment and shaped to accept the ultrasonic waveguidetherein; a transducer attachment dock exposed to the environment andshaped to place the ultrasonic transducer in coaxial alignment with theultrasonic waveguide when the ultrasonic waveguide is disposed withinthe waveguide attachment dock; and an ultrasonic-signal-generatorassembly dock exposed to the environment and shaped to substantiallysimultaneously: selectively removably secure at least the ultrasonictransducer to the handle body; place an end of the ultrasonic transducerwithin the transducer attachment dock; and electrically couple at leastthe ultrasonic transducer to the at least two battery contacts.
 15. Amethod of maintaining a constant movement of a cutting blade of anultrasonic waveguide, which comprises: providing: an ultrasonictransducer operable to convert a received motional current into amovement of a cutting blade of an ultrasonic waveguide; a removablebattery; a disposable handle body with: a portion defining abattery-holding compartment shaped to removably receive the batterytherein; and operable to removably couple the ultrasonic transducer tothe ultrasonic waveguide, the ultrasonic transducer being separable fromthe handle body; the ultrasonic transducer having a first capacitance ina parallel configuration with a series configuration of a resistance, aninductance and a second capacitance, whereby the motional current flowsthrough the series configuration; and a third capacitance in a parallelconfiguration with the first capacitance; supplying current through aset of connection points of the parallel configuration with a variablepower source coupled to the third capacitance and the ultrasonictransducer to, thereby, create the motional current in the ultrasonictransducer; and regulating the motional current with a currentcontroller by varying an output of the power source based upon a productof the current flowing through the third capacitance multiplied by aratio between a value of the first capacitance and a value of the thirdcapacitance subtracted from a total current flowing into the ultrasonictransducer, thereby maintaining a substantially constant rate ofmovement of the cutting blade across a variety of cutting loads.
 16. Themethod according to claim 15, wherein: the current controller comprisesa processor; and the variable power source comprises a phase locked loopcommunicatively coupled to the processor, and which further comprises:determining a frequency of movement of the cutting blade with the phaselocked loop; and storing a last frequency of blade movement in a memorycommunicatively coupled to the processor.
 17. The method according toclaim 15, which further comprises: providing a clamping mechanism havinga range of clamping force values and being operable to place material inphysical contact with the cutting blade; communicatively coupling thecurrent controller to the clamping mechanism; and varying the motionalcurrent with the current controller based upon a given clamping valuewithin the range of clamping values.
 18. A method of maintaining aconstant movement of a cutting blade of an ultrasonic waveguide, whichcomprises: providing: an ultrasonic transducer operable to convert areceived motional current into a movement of a cutting blade of anultrasonic waveguide; and a measurement circuit connected in a parallelconfiguration with the ultrasonic transducer; supplying current througha set of connection points of the parallel configuration with a variablepower source to, thereby, create the motional current in the ultrasonictransducer, the variable power source comprising a removable battery;and regulating the motional current with a current controller by varyingan output of the power source, thereby maintaining a substantiallyconstant rate of movement of the cutting blade across a variety ofcutting loads.